1 | // SPDX-License-Identifier: GPL-2.0 |
2 | // |
3 | // Copyright 2008 Openmoko, Inc. |
4 | // Copyright 2004-2008 Simtec Electronics |
5 | // Ben Dooks <ben@simtec.co.uk> |
6 | // http://armlinux.simtec.co.uk/ |
7 | // |
8 | // S3C common power management (suspend to ram) support. |
9 | |
10 | #include <linux/init.h> |
11 | #include <linux/suspend.h> |
12 | #include <linux/errno.h> |
13 | #include <linux/delay.h> |
14 | #include <linux/of.h> |
15 | #include <linux/serial_s3c.h> |
16 | #include <linux/io.h> |
17 | |
18 | #include <asm/cacheflush.h> |
19 | #include <asm/suspend.h> |
20 | |
21 | #include "map.h" |
22 | #include "regs-clock.h" |
23 | #include "regs-irq.h" |
24 | #include "irqs.h" |
25 | |
26 | #include <asm/irq.h> |
27 | |
28 | #include "cpu.h" |
29 | #include "pm.h" |
30 | #include "pm-core.h" |
31 | |
32 | /* for external use */ |
33 | |
34 | unsigned long s3c_pm_flags; |
35 | |
36 | /* The IRQ ext-int code goes here, it is too small to currently bother |
37 | * with its own file. */ |
38 | |
39 | unsigned long s3c_irqwake_intmask = 0xffffffffL; |
40 | unsigned long s3c_irqwake_eintmask = 0xffffffffL; |
41 | |
42 | int s3c_irqext_wake(struct irq_data *data, unsigned int state) |
43 | { |
44 | unsigned long bit = 1L << IRQ_EINT_BIT(data->irq); |
45 | |
46 | if (!(s3c_irqwake_eintallow & bit)) |
47 | return -ENOENT; |
48 | |
49 | printk(KERN_INFO "wake %s for irq %d\n" , |
50 | state ? "enabled" : "disabled" , data->irq); |
51 | |
52 | if (!state) |
53 | s3c_irqwake_eintmask |= bit; |
54 | else |
55 | s3c_irqwake_eintmask &= ~bit; |
56 | |
57 | return 0; |
58 | } |
59 | |
60 | void (*pm_cpu_prep)(void); |
61 | int (*pm_cpu_sleep)(unsigned long); |
62 | |
63 | #define any_allowed(mask, allow) (((mask) & (allow)) != (allow)) |
64 | |
65 | /* s3c_pm_enter |
66 | * |
67 | * central control for sleep/resume process |
68 | */ |
69 | |
70 | static int s3c_pm_enter(suspend_state_t state) |
71 | { |
72 | int ret; |
73 | /* ensure the debug is initialised (if enabled) */ |
74 | s3c_pm_debug_init_uart(); |
75 | |
76 | S3C_PMDBG("%s(%d)\n" , __func__, state); |
77 | |
78 | if (pm_cpu_prep == NULL || pm_cpu_sleep == NULL) { |
79 | printk(KERN_ERR "%s: error: no cpu sleep function\n" , __func__); |
80 | return -EINVAL; |
81 | } |
82 | |
83 | /* check if we have anything to wake-up with... bad things seem |
84 | * to happen if you suspend with no wakeup (system will often |
85 | * require a full power-cycle) |
86 | */ |
87 | |
88 | if (!of_have_populated_dt() && |
89 | !any_allowed(s3c_irqwake_intmask, s3c_irqwake_intallow) && |
90 | !any_allowed(s3c_irqwake_eintmask, s3c_irqwake_eintallow)) { |
91 | printk(KERN_ERR "%s: No wake-up sources!\n" , __func__); |
92 | printk(KERN_ERR "%s: Aborting sleep\n" , __func__); |
93 | return -EINVAL; |
94 | } |
95 | |
96 | /* save all necessary core registers not covered by the drivers */ |
97 | |
98 | if (!of_have_populated_dt()) { |
99 | samsung_pm_save_gpios(); |
100 | samsung_pm_saved_gpios(); |
101 | } |
102 | |
103 | s3c_pm_save_uarts(is_s3c24xx: false); |
104 | s3c_pm_save_core(); |
105 | |
106 | /* set the irq configuration for wake */ |
107 | |
108 | s3c_pm_configure_extint(); |
109 | |
110 | S3C_PMDBG("sleep: irq wakeup masks: %08lx,%08lx\n" , |
111 | s3c_irqwake_intmask, s3c_irqwake_eintmask); |
112 | |
113 | s3c_pm_arch_prepare_irqs(); |
114 | |
115 | /* call cpu specific preparation */ |
116 | |
117 | pm_cpu_prep(); |
118 | |
119 | /* flush cache back to ram */ |
120 | |
121 | flush_cache_all(); |
122 | |
123 | s3c_pm_check_store(); |
124 | |
125 | /* send the cpu to sleep... */ |
126 | |
127 | s3c_pm_arch_stop_clocks(); |
128 | |
129 | /* this will also act as our return point from when |
130 | * we resume as it saves its own register state and restores it |
131 | * during the resume. */ |
132 | |
133 | ret = cpu_suspend(0, pm_cpu_sleep); |
134 | if (ret) |
135 | return ret; |
136 | |
137 | /* restore the system state */ |
138 | |
139 | s3c_pm_restore_core(); |
140 | s3c_pm_restore_uarts(is_s3c24xx: false); |
141 | |
142 | if (!of_have_populated_dt()) { |
143 | samsung_pm_restore_gpios(); |
144 | s3c_pm_restored_gpios(); |
145 | } |
146 | |
147 | s3c_pm_debug_init_uart(); |
148 | |
149 | /* check what irq (if any) restored the system */ |
150 | |
151 | s3c_pm_arch_show_resume_irqs(); |
152 | |
153 | S3C_PMDBG("%s: post sleep, preparing to return\n" , __func__); |
154 | |
155 | s3c_pm_check_restore(); |
156 | |
157 | /* ok, let's return from sleep */ |
158 | |
159 | S3C_PMDBG("S3C PM Resume (post-restore)\n" ); |
160 | return 0; |
161 | } |
162 | |
163 | static int s3c_pm_prepare(void) |
164 | { |
165 | /* prepare check area if configured */ |
166 | |
167 | s3c_pm_check_prepare(); |
168 | return 0; |
169 | } |
170 | |
171 | static void s3c_pm_finish(void) |
172 | { |
173 | s3c_pm_check_cleanup(); |
174 | } |
175 | |
176 | static const struct platform_suspend_ops s3c_pm_ops = { |
177 | .enter = s3c_pm_enter, |
178 | .prepare = s3c_pm_prepare, |
179 | .finish = s3c_pm_finish, |
180 | .valid = suspend_valid_only_mem, |
181 | }; |
182 | |
183 | /* s3c_pm_init |
184 | * |
185 | * Attach the power management functions. This should be called |
186 | * from the board specific initialisation if the board supports |
187 | * it. |
188 | */ |
189 | |
190 | int __init s3c_pm_init(void) |
191 | { |
192 | printk("S3C Power Management, Copyright 2004 Simtec Electronics\n" ); |
193 | |
194 | suspend_set_ops(ops: &s3c_pm_ops); |
195 | return 0; |
196 | } |
197 | |