LXR linux/drivers/cpuidle/cpuidle-calxeda.c

   1/*
   2 * Copyright 2012 Calxeda, Inc.
   3 *
   4 * Based on arch/arm/plat-mxc/cpuidle.c: #v3.7
   5 * Copyright 2012 Freescale Semiconductor, Inc.
   6 * Copyright 2012 Linaro Ltd.
   7 *
   8 * This program is free software; you can redistribute it and/or modify it
   9 * under the terms and conditions of the GNU General Public License,
  10 * version 2, as published by the Free Software Foundation.
  11 *
  12 * This program is distributed in the hope it will be useful, but WITHOUT
  13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  15 * more details.
  16 *
  17 * You should have received a copy of the GNU General Public License along with
  18 * this program.  If not, see <http://www.gnu.org/licenses/>.
  19 *
  20 * Maintainer: Rob Herring <rob.herring@calxeda.com>
  21 */
  22
  23#include <linux/cpuidle.h>
  24#include <linux/cpu_pm.h>
  25#include <linux/init.h>
  26#include <linux/mm.h>
  27#include <linux/platform_device.h>
  28#include <linux/psci.h>
  29
  30#include <asm/cpuidle.h>
  31#include <asm/suspend.h>
  32
  33#include <uapi/linux/psci.h>
  34
  35#define CALXEDA_IDLE_PARAM \
  36        ((0 << PSCI_0_2_POWER_STATE_ID_SHIFT) | \
  37         (0 << PSCI_0_2_POWER_STATE_AFFL_SHIFT) | \
  38         (PSCI_POWER_STATE_TYPE_POWER_DOWN << PSCI_0_2_POWER_STATE_TYPE_SHIFT))
  39
  40static int calxeda_idle_finish(unsigned long val)
  41{
  42        return psci_ops.cpu_suspend(CALXEDA_IDLE_PARAM, __pa(cpu_resume));
  43}
  44
  45static int calxeda_pwrdown_idle(struct cpuidle_device *dev,
  46                                struct cpuidle_driver *drv,
  47                                int index)
  48{
  49        cpu_pm_enter();
  50        cpu_suspend(0, calxeda_idle_finish);
  51        cpu_pm_exit();
  52
  53        return index;
  54}
  55
  56static struct cpuidle_driver calxeda_idle_driver = {
  57        .name = "calxeda_idle",
  58        .states = {
  59                ARM_CPUIDLE_WFI_STATE,
  60                {
  61                        .name = "PG",
  62                        .desc = "Power Gate",
  63                        .exit_latency = 30,
  64                        .power_usage = 50,
  65                        .target_residency = 200,
  66                        .enter = calxeda_pwrdown_idle,
  67                },
  68        },
  69        .state_count = 2,
  70};
  71
  72static int calxeda_cpuidle_probe(struct platform_device *pdev)
  73{
  74        return cpuidle_register(&calxeda_idle_driver, NULL);
  75}
  76
  77static struct platform_driver calxeda_cpuidle_plat_driver = {
  78        .driver = {
  79                .name = "cpuidle-calxeda",
  80        },
  81        .probe = calxeda_cpuidle_probe,
  82};
  83builtin_platform_driver(calxeda_cpuidle_plat_driver);
  84