1 | // SPDX-License-Identifier: GPL-2.0 |
2 | // |
3 | // Copyright (c) 2010-2014 Samsung Electronics Co., Ltd. |
4 | // http://www.samsung.com |
5 | // |
6 | // S5PV210 - Power Management support |
7 | // |
8 | // Based on arch/arm/mach-s3c2410/pm.c |
9 | // Copyright (c) 2006 Simtec Electronics |
10 | // Ben Dooks <ben@simtec.co.uk> |
11 | |
12 | #include <linux/init.h> |
13 | #include <linux/suspend.h> |
14 | #include <linux/syscore_ops.h> |
15 | #include <linux/io.h> |
16 | #include <linux/soc/samsung/s3c-pm.h> |
17 | |
18 | #include <asm/cacheflush.h> |
19 | #include <asm/suspend.h> |
20 | |
21 | #include "common.h" |
22 | #include "regs-clock.h" |
23 | |
24 | /* helper functions to save and restore register state */ |
25 | struct sleep_save { |
26 | void __iomem *reg; |
27 | unsigned long val; |
28 | }; |
29 | |
30 | #define SAVE_ITEM(x) \ |
31 | { .reg = (x) } |
32 | |
33 | /** |
34 | * s3c_pm_do_save() - save a set of registers for restoration on resume. |
35 | * @ptr: Pointer to an array of registers. |
36 | * @count: Size of the ptr array. |
37 | * |
38 | * Run through the list of registers given, saving their contents in the |
39 | * array for later restoration when we wakeup. |
40 | */ |
41 | static void s3c_pm_do_save(struct sleep_save *ptr, int count) |
42 | { |
43 | for (; count > 0; count--, ptr++) { |
44 | ptr->val = readl_relaxed(ptr->reg); |
45 | S3C_PMDBG("saved %p value %08lx\n" , ptr->reg, ptr->val); |
46 | } |
47 | } |
48 | |
49 | /** |
50 | * s3c_pm_do_restore() - restore register values from the save list. |
51 | * @ptr: Pointer to an array of registers. |
52 | * @count: Size of the ptr array. |
53 | * |
54 | * Restore the register values saved from s3c_pm_do_save(). |
55 | * |
56 | * WARNING: Do not put any debug in here that may effect memory or use |
57 | * peripherals, as things may be changing! |
58 | */ |
59 | |
60 | static void s3c_pm_do_restore_core(const struct sleep_save *ptr, int count) |
61 | { |
62 | for (; count > 0; count--, ptr++) |
63 | writel_relaxed(ptr->val, ptr->reg); |
64 | } |
65 | |
66 | static struct sleep_save s5pv210_core_save[] = { |
67 | /* Clock ETC */ |
68 | SAVE_ITEM(S5P_MDNIE_SEL), |
69 | }; |
70 | |
71 | /* |
72 | * VIC wake-up support (TODO) |
73 | */ |
74 | static u32 s5pv210_irqwake_intmask = 0xffffffff; |
75 | |
76 | static u32 s5pv210_read_eint_wakeup_mask(void) |
77 | { |
78 | return __raw_readl(S5P_EINT_WAKEUP_MASK); |
79 | } |
80 | |
81 | /* |
82 | * Suspend helpers. |
83 | */ |
84 | static int s5pv210_cpu_suspend(unsigned long arg) |
85 | { |
86 | unsigned long tmp; |
87 | |
88 | /* issue the standby signal into the pm unit. Note, we |
89 | * issue a write-buffer drain just in case */ |
90 | |
91 | tmp = 0; |
92 | |
93 | asm("b 1f\n\t" |
94 | ".align 5\n\t" |
95 | "1:\n\t" |
96 | "mcr p15, 0, %0, c7, c10, 5\n\t" |
97 | "mcr p15, 0, %0, c7, c10, 4\n\t" |
98 | "wfi" : : "r" (tmp)); |
99 | |
100 | pr_info("Failed to suspend the system\n" ); |
101 | return 1; /* Aborting suspend */ |
102 | } |
103 | |
104 | static void s5pv210_pm_prepare(void) |
105 | { |
106 | unsigned int tmp; |
107 | |
108 | /* |
109 | * Set wake-up mask registers |
110 | * S5P_EINT_WAKEUP_MASK is set by pinctrl driver in late suspend. |
111 | */ |
112 | __raw_writel(val: s5pv210_irqwake_intmask, S5P_WAKEUP_MASK); |
113 | |
114 | /* ensure at least INFORM0 has the resume address */ |
115 | __raw_writel(__pa_symbol(s5pv210_cpu_resume), S5P_INFORM0); |
116 | |
117 | tmp = __raw_readl(S5P_SLEEP_CFG); |
118 | tmp &= ~(S5P_SLEEP_CFG_OSC_EN | S5P_SLEEP_CFG_USBOSC_EN); |
119 | __raw_writel(val: tmp, S5P_SLEEP_CFG); |
120 | |
121 | /* WFI for SLEEP mode configuration by SYSCON */ |
122 | tmp = __raw_readl(S5P_PWR_CFG); |
123 | tmp &= S5P_CFG_WFI_CLEAN; |
124 | tmp |= S5P_CFG_WFI_SLEEP; |
125 | __raw_writel(val: tmp, S5P_PWR_CFG); |
126 | |
127 | /* SYSCON interrupt handling disable */ |
128 | tmp = __raw_readl(S5P_OTHERS); |
129 | tmp |= S5P_OTHER_SYSC_INTOFF; |
130 | __raw_writel(val: tmp, S5P_OTHERS); |
131 | |
132 | s3c_pm_do_save(ptr: s5pv210_core_save, ARRAY_SIZE(s5pv210_core_save)); |
133 | } |
134 | |
135 | /* |
136 | * Suspend operations. |
137 | */ |
138 | static int s5pv210_suspend_enter(suspend_state_t state) |
139 | { |
140 | u32 eint_wakeup_mask = s5pv210_read_eint_wakeup_mask(); |
141 | int ret; |
142 | |
143 | S3C_PMDBG("%s: suspending the system...\n" , __func__); |
144 | |
145 | S3C_PMDBG("%s: wakeup masks: %08x,%08x\n" , __func__, |
146 | s5pv210_irqwake_intmask, eint_wakeup_mask); |
147 | |
148 | if (s5pv210_irqwake_intmask == -1U |
149 | && eint_wakeup_mask == -1U) { |
150 | pr_err("%s: No wake-up sources!\n" , __func__); |
151 | pr_err("%s: Aborting sleep\n" , __func__); |
152 | return -EINVAL; |
153 | } |
154 | |
155 | s3c_pm_save_uarts(is_s3c24xx: false); |
156 | s5pv210_pm_prepare(); |
157 | flush_cache_all(); |
158 | s3c_pm_check_store(); |
159 | |
160 | ret = cpu_suspend(0, s5pv210_cpu_suspend); |
161 | if (ret) |
162 | return ret; |
163 | |
164 | s3c_pm_restore_uarts(is_s3c24xx: false); |
165 | |
166 | S3C_PMDBG("%s: wakeup stat: %08x\n" , __func__, |
167 | __raw_readl(S5P_WAKEUP_STAT)); |
168 | |
169 | s3c_pm_check_restore(); |
170 | |
171 | S3C_PMDBG("%s: resuming the system...\n" , __func__); |
172 | |
173 | return 0; |
174 | } |
175 | |
176 | static int s5pv210_suspend_prepare(void) |
177 | { |
178 | s3c_pm_check_prepare(); |
179 | |
180 | return 0; |
181 | } |
182 | |
183 | static void s5pv210_suspend_finish(void) |
184 | { |
185 | s3c_pm_check_cleanup(); |
186 | } |
187 | |
188 | static const struct platform_suspend_ops s5pv210_suspend_ops = { |
189 | .enter = s5pv210_suspend_enter, |
190 | .prepare = s5pv210_suspend_prepare, |
191 | .finish = s5pv210_suspend_finish, |
192 | .valid = suspend_valid_only_mem, |
193 | }; |
194 | |
195 | /* |
196 | * Syscore operations used to delay restore of certain registers. |
197 | */ |
198 | static void s5pv210_pm_resume(void) |
199 | { |
200 | s3c_pm_do_restore_core(ptr: s5pv210_core_save, ARRAY_SIZE(s5pv210_core_save)); |
201 | } |
202 | |
203 | static struct syscore_ops s5pv210_pm_syscore_ops = { |
204 | .resume = s5pv210_pm_resume, |
205 | }; |
206 | |
207 | /* |
208 | * Initialization entry point. |
209 | */ |
210 | void __init s5pv210_pm_init(void) |
211 | { |
212 | register_syscore_ops(ops: &s5pv210_pm_syscore_ops); |
213 | suspend_set_ops(ops: &s5pv210_suspend_ops); |
214 | } |
215 | |