1 /* linux/arch/arm/mach-exynos/cpuidle.c
3 * Copyright (c) 2011 Samsung Electronics Co., Ltd.
4 * http://www.samsung.com
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <linux/cpuidle.h>
14 #include <linux/cpu_pm.h>
16 #include <linux/export.h>
17 #include <linux/module.h>
18 #include <linux/time.h>
19 #include <linux/platform_device.h>
21 #include <asm/proc-fns.h>
22 #include <asm/suspend.h>
23 #include <asm/unified.h>
24 #include <asm/cpuidle.h>
34 #define REG_DIRECTGO_ADDR (samsung_rev() == EXYNOS4210_REV_1_1 ? \
35 S5P_INFORM7 : (samsung_rev() == EXYNOS4210_REV_1_0 ? \
36 (S5P_VA_SYSRAM + 0x24) : S5P_INFORM0))
37 #define REG_DIRECTGO_FLAG (samsung_rev() == EXYNOS4210_REV_1_1 ? \
38 S5P_INFORM6 : (samsung_rev() == EXYNOS4210_REV_1_0 ? \
39 (S5P_VA_SYSRAM + 0x20) : S5P_INFORM1))
41 #define S5P_CHECK_AFTR 0xFCBA0D10
43 /* Ext-GIC nIRQ/nFIQ is the only wakeup source in AFTR */
44 static void exynos_set_wakeupmask(long mask)
46 __raw_writel(mask, S5P_WAKEUP_MASK);
49 static void exynos_cpu_set_boot_vector(long flags)
51 __raw_writel(virt_to_phys(exynos_cpu_resume), REG_DIRECTGO_ADDR);
52 __raw_writel(flags, REG_DIRECTGO_FLAG);
55 static int idle_finisher(unsigned long flags)
57 exynos_set_wakeupmask(0x0000ff3e);
58 exynos_cpu_set_boot_vector(S5P_CHECK_AFTR);
59 /* Set value of power down register for aftr mode */
60 exynos_sys_powerdown_conf(SYS_AFTR);
67 static int exynos_enter_core0_aftr(struct cpuidle_device *dev,
68 struct cpuidle_driver *drv,
73 /* Setting Central Sequence Register for power down mode */
74 tmp = __raw_readl(S5P_CENTRAL_SEQ_CONFIGURATION);
75 tmp &= ~S5P_CENTRAL_LOWPWR_CFG;
76 __raw_writel(tmp, S5P_CENTRAL_SEQ_CONFIGURATION);
79 cpu_suspend(0, idle_finisher);
83 * If PMU failed while entering sleep mode, WFI will be
84 * ignored by PMU and then exiting cpu_do_idle().
85 * S5P_CENTRAL_LOWPWR_CFG bit will not be set automatically
88 tmp = __raw_readl(S5P_CENTRAL_SEQ_CONFIGURATION);
89 if (!(tmp & S5P_CENTRAL_LOWPWR_CFG)) {
90 tmp |= S5P_CENTRAL_LOWPWR_CFG;
91 __raw_writel(tmp, S5P_CENTRAL_SEQ_CONFIGURATION);
92 /* Clear wakeup state register */
93 __raw_writel(0x0, S5P_WAKEUP_STAT);
99 static int exynos_enter_lowpower(struct cpuidle_device *dev,
100 struct cpuidle_driver *drv,
103 int new_index = index;
105 /* AFTR can only be entered when cores other than CPU0 are offline */
106 if (num_online_cpus() > 1 || dev->cpu != 0)
107 new_index = drv->safe_state_index;
110 return arm_cpuidle_simple_enter(dev, drv, new_index);
112 return exynos_enter_core0_aftr(dev, drv, new_index);
115 static struct cpuidle_driver exynos_idle_driver = {
116 .name = "exynos_idle",
117 .owner = THIS_MODULE,
119 [0] = ARM_CPUIDLE_WFI_STATE,
121 .enter = exynos_enter_lowpower,
123 .target_residency = 100000,
124 .flags = CPUIDLE_FLAG_TIME_VALID,
126 .desc = "ARM power down",
130 .safe_state_index = 0,
133 static int exynos_cpuidle_probe(struct platform_device *pdev)
137 if (soc_is_exynos5440())
138 exynos_idle_driver.state_count = 1;
140 ret = cpuidle_register(&exynos_idle_driver, NULL);
142 dev_err(&pdev->dev, "failed to register cpuidle driver\n");
149 static struct platform_driver exynos_cpuidle_driver = {
150 .probe = exynos_cpuidle_probe,
152 .name = "exynos_cpuidle",
153 .owner = THIS_MODULE,
157 module_platform_driver(exynos_cpuidle_driver);