144 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			144 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0-only
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| /*
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|  * Copyright (c) 2011-2014 Samsung Electronics Co., Ltd.
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|  *		http://www.samsung.com
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|  *
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|  * Coupled cpuidle support based on the work of:
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|  *	Colin Cross <ccross@android.com>
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|  *	Daniel Lezcano <daniel.lezcano@linaro.org>
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| */
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| 
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| #include <linux/cpuidle.h>
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| #include <linux/cpu_pm.h>
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| #include <linux/export.h>
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| #include <linux/init.h>
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| #include <linux/platform_device.h>
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| #include <linux/of.h>
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| #include <linux/platform_data/cpuidle-exynos.h>
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| 
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| #include <asm/suspend.h>
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| #include <asm/cpuidle.h>
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| 
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| static atomic_t exynos_idle_barrier;
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| 
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| static struct cpuidle_exynos_data *exynos_cpuidle_pdata;
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| static void (*exynos_enter_aftr)(void);
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| 
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| static int exynos_enter_coupled_lowpower(struct cpuidle_device *dev,
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| 					 struct cpuidle_driver *drv,
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| 					 int index)
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| {
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| 	int ret;
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| 
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| 	exynos_cpuidle_pdata->pre_enter_aftr();
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| 
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| 	/*
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| 	 * Waiting all cpus to reach this point at the same moment
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| 	 */
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| 	cpuidle_coupled_parallel_barrier(dev, &exynos_idle_barrier);
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| 
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| 	/*
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| 	 * Both cpus will reach this point at the same time
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| 	 */
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| 	ret = dev->cpu ? exynos_cpuidle_pdata->cpu1_powerdown()
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| 		       : exynos_cpuidle_pdata->cpu0_enter_aftr();
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| 	if (ret)
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| 		index = ret;
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| 
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| 	/*
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| 	 * Waiting all cpus to finish the power sequence before going further
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| 	 */
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| 	cpuidle_coupled_parallel_barrier(dev, &exynos_idle_barrier);
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| 
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| 	exynos_cpuidle_pdata->post_enter_aftr();
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| 
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| 	return index;
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| }
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| 
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| static int exynos_enter_lowpower(struct cpuidle_device *dev,
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| 				struct cpuidle_driver *drv,
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| 				int index)
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| {
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| 	int new_index = index;
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| 
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| 	/* AFTR can only be entered when cores other than CPU0 are offline */
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| 	if (num_online_cpus() > 1 || dev->cpu != 0)
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| 		new_index = drv->safe_state_index;
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| 
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| 	if (new_index == 0)
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| 		return arm_cpuidle_simple_enter(dev, drv, new_index);
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| 
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| 	exynos_enter_aftr();
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| 
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| 	return new_index;
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| }
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| 
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| static struct cpuidle_driver exynos_idle_driver = {
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| 	.name			= "exynos_idle",
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| 	.owner			= THIS_MODULE,
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| 	.states = {
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| 		[0] = ARM_CPUIDLE_WFI_STATE,
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| 		[1] = {
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| 			.enter			= exynos_enter_lowpower,
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| 			.exit_latency		= 300,
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| 			.target_residency	= 10000,
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| 			.name			= "C1",
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| 			.desc			= "ARM power down",
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| 		},
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| 	},
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| 	.state_count = 2,
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| 	.safe_state_index = 0,
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| };
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| 
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| static struct cpuidle_driver exynos_coupled_idle_driver = {
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| 	.name			= "exynos_coupled_idle",
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| 	.owner			= THIS_MODULE,
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| 	.states = {
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| 		[0] = ARM_CPUIDLE_WFI_STATE,
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| 		[1] = {
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| 			.enter			= exynos_enter_coupled_lowpower,
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| 			.exit_latency		= 5000,
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| 			.target_residency	= 10000,
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| 			.flags			= CPUIDLE_FLAG_COUPLED |
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| 						  CPUIDLE_FLAG_TIMER_STOP,
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| 			.name			= "C1",
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| 			.desc			= "ARM power down",
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| 		},
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| 	},
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| 	.state_count = 2,
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| 	.safe_state_index = 0,
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| };
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| 
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| static int exynos_cpuidle_probe(struct platform_device *pdev)
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| {
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| 	int ret;
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| 
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| 	if (IS_ENABLED(CONFIG_SMP) &&
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| 	    (of_machine_is_compatible("samsung,exynos4210") ||
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| 	     of_machine_is_compatible("samsung,exynos3250"))) {
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| 		exynos_cpuidle_pdata = pdev->dev.platform_data;
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| 
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| 		ret = cpuidle_register(&exynos_coupled_idle_driver,
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| 				       cpu_possible_mask);
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| 	} else {
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| 		exynos_enter_aftr = (void *)(pdev->dev.platform_data);
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| 
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| 		ret = cpuidle_register(&exynos_idle_driver, NULL);
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| 	}
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| 
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| 	if (ret) {
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| 		dev_err(&pdev->dev, "failed to register cpuidle driver\n");
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| 		return ret;
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| 	}
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| 
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| 	return 0;
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| }
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| 
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| static struct platform_driver exynos_cpuidle_driver = {
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| 	.probe	= exynos_cpuidle_probe,
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| 	.driver = {
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| 		.name = "exynos_cpuidle",
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| 	},
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| };
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| builtin_platform_driver(exynos_cpuidle_driver);
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