Merge tag 'soc2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
[~shefty/rdma-dev.git] / arch / arm / mach-exynos / cpuidle.c
1 /* linux/arch/arm/mach-exynos4/cpuidle.c
2  *
3  * Copyright (c) 2011 Samsung Electronics Co., Ltd.
4  *              http://www.samsung.com
5  *
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.
9 */
10
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <linux/cpuidle.h>
14 #include <linux/cpu_pm.h>
15 #include <linux/io.h>
16 #include <linux/export.h>
17 #include <linux/time.h>
18
19 #include <asm/proc-fns.h>
20 #include <asm/smp_scu.h>
21 #include <asm/suspend.h>
22 #include <asm/unified.h>
23 #include <asm/cpuidle.h>
24 #include <mach/regs-clock.h>
25 #include <mach/regs-pmu.h>
26 #include <mach/pmu.h>
27
28 #include <plat/cpu.h>
29
30 #define REG_DIRECTGO_ADDR       (samsung_rev() == EXYNOS4210_REV_1_1 ? \
31                         S5P_INFORM7 : (samsung_rev() == EXYNOS4210_REV_1_0 ? \
32                         (S5P_VA_SYSRAM + 0x24) : S5P_INFORM0))
33 #define REG_DIRECTGO_FLAG       (samsung_rev() == EXYNOS4210_REV_1_1 ? \
34                         S5P_INFORM6 : (samsung_rev() == EXYNOS4210_REV_1_0 ? \
35                         (S5P_VA_SYSRAM + 0x20) : S5P_INFORM1))
36
37 #define S5P_CHECK_AFTR          0xFCBA0D10
38
39 static int exynos4_enter_lowpower(struct cpuidle_device *dev,
40                                 struct cpuidle_driver *drv,
41                                 int index);
42
43 static struct cpuidle_state exynos4_cpuidle_set[] __initdata = {
44         [0] = ARM_CPUIDLE_WFI_STATE,
45         [1] = {
46                 .enter                  = exynos4_enter_lowpower,
47                 .exit_latency           = 300,
48                 .target_residency       = 100000,
49                 .flags                  = CPUIDLE_FLAG_TIME_VALID,
50                 .name                   = "C1",
51                 .desc                   = "ARM power down",
52         },
53 };
54
55 static DEFINE_PER_CPU(struct cpuidle_device, exynos4_cpuidle_device);
56
57 static struct cpuidle_driver exynos4_idle_driver = {
58         .name                   = "exynos4_idle",
59         .owner                  = THIS_MODULE,
60         .en_core_tk_irqen       = 1,
61 };
62
63 /* Ext-GIC nIRQ/nFIQ is the only wakeup source in AFTR */
64 static void exynos4_set_wakeupmask(void)
65 {
66         __raw_writel(0x0000ff3e, S5P_WAKEUP_MASK);
67 }
68
69 static unsigned int g_pwr_ctrl, g_diag_reg;
70
71 static void save_cpu_arch_register(void)
72 {
73         /*read power control register*/
74         asm("mrc p15, 0, %0, c15, c0, 0" : "=r"(g_pwr_ctrl) : : "cc");
75         /*read diagnostic register*/
76         asm("mrc p15, 0, %0, c15, c0, 1" : "=r"(g_diag_reg) : : "cc");
77         return;
78 }
79
80 static void restore_cpu_arch_register(void)
81 {
82         /*write power control register*/
83         asm("mcr p15, 0, %0, c15, c0, 0" : : "r"(g_pwr_ctrl) : "cc");
84         /*write diagnostic register*/
85         asm("mcr p15, 0, %0, c15, c0, 1" : : "r"(g_diag_reg) : "cc");
86         return;
87 }
88
89 static int idle_finisher(unsigned long flags)
90 {
91         cpu_do_idle();
92         return 1;
93 }
94
95 static int exynos4_enter_core0_aftr(struct cpuidle_device *dev,
96                                 struct cpuidle_driver *drv,
97                                 int index)
98 {
99         unsigned long tmp;
100
101         exynos4_set_wakeupmask();
102
103         /* Set value of power down register for aftr mode */
104         exynos_sys_powerdown_conf(SYS_AFTR);
105
106         __raw_writel(virt_to_phys(s3c_cpu_resume), REG_DIRECTGO_ADDR);
107         __raw_writel(S5P_CHECK_AFTR, REG_DIRECTGO_FLAG);
108
109         save_cpu_arch_register();
110
111         /* Setting Central Sequence Register for power down mode */
112         tmp = __raw_readl(S5P_CENTRAL_SEQ_CONFIGURATION);
113         tmp &= ~S5P_CENTRAL_LOWPWR_CFG;
114         __raw_writel(tmp, S5P_CENTRAL_SEQ_CONFIGURATION);
115
116         cpu_pm_enter();
117         cpu_suspend(0, idle_finisher);
118
119 #ifdef CONFIG_SMP
120         if (!soc_is_exynos5250())
121                 scu_enable(S5P_VA_SCU);
122 #endif
123         cpu_pm_exit();
124
125         restore_cpu_arch_register();
126
127         /*
128          * If PMU failed while entering sleep mode, WFI will be
129          * ignored by PMU and then exiting cpu_do_idle().
130          * S5P_CENTRAL_LOWPWR_CFG bit will not be set automatically
131          * in this situation.
132          */
133         tmp = __raw_readl(S5P_CENTRAL_SEQ_CONFIGURATION);
134         if (!(tmp & S5P_CENTRAL_LOWPWR_CFG)) {
135                 tmp |= S5P_CENTRAL_LOWPWR_CFG;
136                 __raw_writel(tmp, S5P_CENTRAL_SEQ_CONFIGURATION);
137         }
138
139         /* Clear wakeup state register */
140         __raw_writel(0x0, S5P_WAKEUP_STAT);
141
142         return index;
143 }
144
145 static int exynos4_enter_lowpower(struct cpuidle_device *dev,
146                                 struct cpuidle_driver *drv,
147                                 int index)
148 {
149         int new_index = index;
150
151         /* This mode only can be entered when other core's are offline */
152         if (num_online_cpus() > 1)
153                 new_index = drv->safe_state_index;
154
155         if (new_index == 0)
156                 return arm_cpuidle_simple_enter(dev, drv, new_index);
157         else
158                 return exynos4_enter_core0_aftr(dev, drv, new_index);
159 }
160
161 static void __init exynos5_core_down_clk(void)
162 {
163         unsigned int tmp;
164
165         /*
166          * Enable arm clock down (in idle) and set arm divider
167          * ratios in WFI/WFE state.
168          */
169         tmp = PWR_CTRL1_CORE2_DOWN_RATIO | \
170               PWR_CTRL1_CORE1_DOWN_RATIO | \
171               PWR_CTRL1_DIV2_DOWN_EN     | \
172               PWR_CTRL1_DIV1_DOWN_EN     | \
173               PWR_CTRL1_USE_CORE1_WFE    | \
174               PWR_CTRL1_USE_CORE0_WFE    | \
175               PWR_CTRL1_USE_CORE1_WFI    | \
176               PWR_CTRL1_USE_CORE0_WFI;
177         __raw_writel(tmp, EXYNOS5_PWR_CTRL1);
178
179         /*
180          * Enable arm clock up (on exiting idle). Set arm divider
181          * ratios when not in idle along with the standby duration
182          * ratios.
183          */
184         tmp = PWR_CTRL2_DIV2_UP_EN       | \
185               PWR_CTRL2_DIV1_UP_EN       | \
186               PWR_CTRL2_DUR_STANDBY2_VAL | \
187               PWR_CTRL2_DUR_STANDBY1_VAL | \
188               PWR_CTRL2_CORE2_UP_RATIO   | \
189               PWR_CTRL2_CORE1_UP_RATIO;
190         __raw_writel(tmp, EXYNOS5_PWR_CTRL2);
191 }
192
193 static int __init exynos4_init_cpuidle(void)
194 {
195         int i, max_cpuidle_state, cpu_id;
196         struct cpuidle_device *device;
197         struct cpuidle_driver *drv = &exynos4_idle_driver;
198
199         if (soc_is_exynos5250())
200                 exynos5_core_down_clk();
201
202         /* Setup cpuidle driver */
203         drv->state_count = (sizeof(exynos4_cpuidle_set) /
204                                        sizeof(struct cpuidle_state));
205         max_cpuidle_state = drv->state_count;
206         for (i = 0; i < max_cpuidle_state; i++) {
207                 memcpy(&drv->states[i], &exynos4_cpuidle_set[i],
208                                 sizeof(struct cpuidle_state));
209         }
210         drv->safe_state_index = 0;
211         cpuidle_register_driver(&exynos4_idle_driver);
212
213         for_each_cpu(cpu_id, cpu_online_mask) {
214                 device = &per_cpu(exynos4_cpuidle_device, cpu_id);
215                 device->cpu = cpu_id;
216
217                 if (cpu_id == 0)
218                         device->state_count = (sizeof(exynos4_cpuidle_set) /
219                                                sizeof(struct cpuidle_state));
220                 else
221                         device->state_count = 1;        /* Support IDLE only */
222
223                 if (cpuidle_register_device(device)) {
224                         printk(KERN_ERR "CPUidle register device failed\n,");
225                         return -EIO;
226                 }
227         }
228
229         return 0;
230 }
231 device_initcall(exynos4_init_cpuidle);