/* * Copyright (c) 2011-2014 Samsung Electronics Co., Ltd. * http://www.samsung.com * * Coupled cpuidle support based on the work of: * Colin Cross <ccross@android.com> * Daniel Lezcano <daniel.lezcano@linaro.org> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include <linux/cpuidle.h> #include <linux/cpu_pm.h> #include <linux/export.h> #include <linux/init.h> #include <linux/platform_device.h> #include <linux/of.h> #include <linux/platform_data/cpuidle-exynos.h> #include <asm/suspend.h> #include <asm/cpuidle.h> static atomic_t exynos_idle_barrier; static struct cpuidle_exynos_data *exynos_cpuidle_pdata; static void (*exynos_enter_aftr)(void); static int exynos_enter_coupled_lowpower(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index) { int ret; exynos_cpuidle_pdata->pre_enter_aftr(); /* * Waiting all cpus to reach this point at the same moment */ cpuidle_coupled_parallel_barrier(dev, &exynos_idle_barrier); /* * Both cpus will reach this point at the same time */ ret = dev->cpu ? exynos_cpuidle_pdata->cpu1_powerdown() : exynos_cpuidle_pdata->cpu0_enter_aftr(); if (ret) index = ret; /* * Waiting all cpus to finish the power sequence before going further */ cpuidle_coupled_parallel_barrier(dev, &exynos_idle_barrier); exynos_cpuidle_pdata->post_enter_aftr(); return index; } static int exynos_enter_lowpower(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index) { int new_index = index; /* AFTR can only be entered when cores other than CPU0 are offline */ if (num_online_cpus() > 1 || dev->cpu != 0) new_index = drv->safe_state_index; if (new_index == 0) return arm_cpuidle_simple_enter(dev, drv, new_index); exynos_enter_aftr(); return new_index; } static struct cpuidle_driver exynos_idle_driver = { .name = "exynos_idle", .owner = THIS_MODULE, .states = { [0] = ARM_CPUIDLE_WFI_STATE, [1] = { .enter = exynos_enter_lowpower, .exit_latency = 300, .target_residency = 100000, .name = "C1", .desc = "ARM power down", }, }, .state_count = 2, .safe_state_index = 0, }; static struct cpuidle_driver exynos_coupled_idle_driver = { .name = "exynos_coupled_idle", .owner = THIS_MODULE, .states = { [0] = ARM_CPUIDLE_WFI_STATE, [1] = { .enter = exynos_enter_coupled_lowpower, .exit_latency = 5000, .target_residency = 10000, .flags = CPUIDLE_FLAG_COUPLED | CPUIDLE_FLAG_TIMER_STOP, .name = "C1", .desc = "ARM power down", }, }, .state_count = 2, .safe_state_index = 0, }; static int exynos_cpuidle_probe(struct platform_device *pdev) { int ret; if (IS_ENABLED(CONFIG_SMP) && (of_machine_is_compatible("samsung,exynos4210") || of_machine_is_compatible("samsung,exynos3250"))) { exynos_cpuidle_pdata = pdev->dev.platform_data; ret = cpuidle_register(&exynos_coupled_idle_driver, cpu_possible_mask); } else { exynos_enter_aftr = (void *)(pdev->dev.platform_data); ret = cpuidle_register(&exynos_idle_driver, NULL); } if (ret) { dev_err(&pdev->dev, "failed to register cpuidle driver\n"); return ret; } return 0; } static struct platform_driver exynos_cpuidle_driver = { .probe = exynos_cpuidle_probe, .driver = { .name = "exynos_cpuidle", }, }; builtin_platform_driver(exynos_cpuidle_driver);