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 <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/cpuidle.h>
  20 #include <linux/cpu_pm.h>
  21 #include <linux/clockchips.h>
  22 #include <asm/firmware.h>
  23
  24 #include <asm/cpuidle.h>
  25 #include <asm/suspend.h>
  26 #include <asm/smp_plat.h>
  27
  28 #include "pm.h"
  29 #include "sleep.h"
  30
  31 #ifdef CONFIG_PM_SLEEP
  32 #define TEGRA114_MAX_STATES 2
  33 #else
  34 #define TEGRA114_MAX_STATES 1
  35 #endif
  36
  37 #ifdef CONFIG_PM_SLEEP
  38 static int tegra114_idle_power_down(struct cpuidle_device *dev,
  39                                     struct cpuidle_driver *drv,
  40                                     int index)
  41 {
  42         local_fiq_disable();
  43
  44         tegra_set_cpu_in_lp2();
  45         cpu_pm_enter();
  46
  47         clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu);
  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) == -ENOSYS)
  53                 cpu_suspend(0, tegra30_sleep_cpu_secondary_finish);
  54
  55         clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &dev->cpu);
  56
  57         cpu_pm_exit();
  58         tegra_clear_cpu_in_lp2();
  59
  60         local_fiq_enable();
  61
  62         return index;
  63 }
  64 #endif
  65
  66 static struct cpuidle_driver tegra_idle_driver = {
  67         .name = "tegra_idle",
  68         .owner = THIS_MODULE,
  69         .state_count = TEGRA114_MAX_STATES,
  70         .states = {
  71                 [0] = ARM_CPUIDLE_WFI_STATE_PWR(600),
  72 #ifdef CONFIG_PM_SLEEP
  73                 [1] = {
  74                         .enter                  = tegra114_idle_power_down,
  75                         .exit_latency           = 500,
  76                         .target_residency       = 1000,
  77                         .power_usage            = 0,
  78                         .flags                  = CPUIDLE_FLAG_TIME_VALID,
  79                         .name                   = "powered-down",
  80                         .desc                   = "CPU power gated",
  81                 },
  82 #endif
  83         },
  84 };
  85
  86 int __init tegra114_cpuidle_init(void)
  87 {
  88         return cpuidle_register(&tegra_idle_driver, NULL);
  89 }