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 "cpuidle.h"
  30 #include "pm.h"
  31 #include "sleep.h"
  32
  33 #ifdef CONFIG_PM_SLEEP
  34 #define TEGRA114_MAX_STATES 2
  35 #else
  36 #define TEGRA114_MAX_STATES 1
  37 #endif
  38
  39 #ifdef CONFIG_PM_SLEEP
  40 static int tegra114_idle_power_down(struct cpuidle_device *dev,
  41                                     struct cpuidle_driver *drv,
  42                                     int index)
  43 {
  44         local_fiq_disable();
  45
  46         tegra_set_cpu_in_lp2();
  47         cpu_pm_enter();
  48
  49         call_firmware_op(prepare_idle);
  50
  51         /* Do suspend by ourselves if the firmware does not implement it */
  52         if (call_firmware_op(do_idle, 0) == -ENOSYS)
  53                 cpu_suspend(0, tegra30_sleep_cpu_secondary_finish);
  54
  55         cpu_pm_exit();
  56         tegra_clear_cpu_in_lp2();
  57
  58         local_fiq_enable();
  59
  60         return index;
  61 }
  62
  63 static void tegra114_idle_enter_s2idle(struct cpuidle_device *dev,
  64                                        struct cpuidle_driver *drv,
  65                                        int index)
  66 {
  67        tegra114_idle_power_down(dev, drv, index);
  68 }
  69 #endif
  70
  71 static struct cpuidle_driver tegra_idle_driver = {
  72         .name = "tegra_idle",
  73         .owner = THIS_MODULE,
  74         .state_count = TEGRA114_MAX_STATES,
  75         .states = {
  76                 [0] = ARM_CPUIDLE_WFI_STATE_PWR(600),
  77 #ifdef CONFIG_PM_SLEEP
  78                 [1] = {
  79                         .enter                  = tegra114_idle_power_down,
  80                         .enter_s2idle           = tegra114_idle_enter_s2idle,
  81                         .exit_latency           = 500,
  82                         .target_residency       = 1000,
  83                         .flags                  = CPUIDLE_FLAG_TIMER_STOP,
  84                         .power_usage            = 0,
  85                         .name                   = "powered-down",
  86                         .desc                   = "CPU power gated",
  87                 },
  88 #endif
  89         },
  90 };
  91
  92 int __init tegra114_cpuidle_init(void)
  93 {
  94         if (!psci_smp_available())
  95                 return cpuidle_register(&tegra_idle_driver, NULL);
  96
  97         return 0;
  98 }