arch/arm/mach-imx/cpuidle-imx6sl.c

   1 /*
   2  * Copyright (C) 2014 Freescale Semiconductor, Inc.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8
   9 #include <linux/cpuidle.h>
  10 #include <linux/module.h>
  11 #include <asm/cpuidle.h>
  12 #include <asm/proc-fns.h>
  13
  14 #include "common.h"
  15 #include "cpuidle.h"
  16
  17 static int imx6sl_enter_wait(struct cpuidle_device *dev,
  18                             struct cpuidle_driver *drv, int index)
  19 {
  20         imx6q_set_lpm(WAIT_UNCLOCKED);
  21         /*
  22          * Software workaround for ERR005311, see function
  23          * description for details.
  24          */
  25         imx6sl_set_wait_clk(true);
  26         cpu_do_idle();
  27         imx6sl_set_wait_clk(false);
  28         imx6q_set_lpm(WAIT_CLOCKED);
  29
  30         return index;
  31 }
  32
  33 static struct cpuidle_driver imx6sl_cpuidle_driver = {
  34         .name = "imx6sl_cpuidle",
  35         .owner = THIS_MODULE,
  36         .states = {
  37                 /* WFI */
  38                 ARM_CPUIDLE_WFI_STATE,
  39                 /* WAIT */
  40                 {
  41                         .exit_latency = 50,
  42                         .target_residency = 75,
  43                         .flags = CPUIDLE_FLAG_TIME_VALID |
  44                                 CPUIDLE_FLAG_TIMER_STOP,
  45                         .enter = imx6sl_enter_wait,
  46                         .name = "WAIT",
  47                         .desc = "Clock off",
  48                 },
  49         },
  50         .state_count = 2,
  51         .safe_state_index = 0,
  52 };
  53
  54 int __init imx6sl_cpuidle_init(void)
  55 {
  56         return cpuidle_register(&imx6sl_cpuidle_driver, NULL);
  57 }