1 | /* |
2 | * PXA250/210 Power Management Routines |
3 | * |
4 | * Original code for the SA11x0: |
5 | * Copyright (c) 2001 Cliff Brake <cbrake@accelent.com> |
6 | * |
7 | * Modified for the PXA250 by Nicolas Pitre: |
8 | * Copyright (c) 2002 Monta Vista Software, Inc. |
9 | * |
10 | * This program is free software; you can redistribute it and/or |
11 | * modify it under the terms of the GNU General Public License. |
12 | */ |
13 | #include <linux/init.h> |
14 | #include <linux/module.h> |
15 | #include <linux/suspend.h> |
16 | #include <linux/errno.h> |
17 | #include <linux/slab.h> |
18 | |
19 | #include "pm.h" |
20 | |
21 | struct pxa_cpu_pm_fns *pxa_cpu_pm_fns; |
22 | static unsigned long *sleep_save; |
23 | |
24 | int pxa_pm_enter(suspend_state_t state) |
25 | { |
26 | unsigned long sleep_save_checksum = 0, checksum = 0; |
27 | int i; |
28 | |
29 | #ifdef CONFIG_IWMMXT |
30 | /* force any iWMMXt context to ram **/ |
31 | if (elf_hwcap & HWCAP_IWMMXT) |
32 | iwmmxt_task_disable(NULL); |
33 | #endif |
34 | |
35 | /* skip registers saving for standby */ |
36 | if (state != PM_SUSPEND_STANDBY && pxa_cpu_pm_fns->save) { |
37 | pxa_cpu_pm_fns->save(sleep_save); |
38 | /* before sleeping, calculate and save a checksum */ |
39 | for (i = 0; i < pxa_cpu_pm_fns->save_count - 1; i++) |
40 | sleep_save_checksum += sleep_save[i]; |
41 | } |
42 | |
43 | /* *** go zzz *** */ |
44 | pxa_cpu_pm_fns->enter(state); |
45 | |
46 | if (state != PM_SUSPEND_STANDBY && pxa_cpu_pm_fns->restore) { |
47 | /* after sleeping, validate the checksum */ |
48 | for (i = 0; i < pxa_cpu_pm_fns->save_count - 1; i++) |
49 | checksum += sleep_save[i]; |
50 | |
51 | /* if invalid, display message and wait for a hardware reset */ |
52 | if (checksum != sleep_save_checksum) { |
53 | |
54 | while (1) |
55 | pxa_cpu_pm_fns->enter(state); |
56 | } |
57 | pxa_cpu_pm_fns->restore(sleep_save); |
58 | } |
59 | |
60 | pr_debug("*** made it back from resume\n" ); |
61 | |
62 | return 0; |
63 | } |
64 | |
65 | EXPORT_SYMBOL_GPL(pxa_pm_enter); |
66 | |
67 | static int pxa_pm_valid(suspend_state_t state) |
68 | { |
69 | if (pxa_cpu_pm_fns) |
70 | return pxa_cpu_pm_fns->valid(state); |
71 | |
72 | return -EINVAL; |
73 | } |
74 | |
75 | int pxa_pm_prepare(void) |
76 | { |
77 | int ret = 0; |
78 | |
79 | if (pxa_cpu_pm_fns && pxa_cpu_pm_fns->prepare) |
80 | ret = pxa_cpu_pm_fns->prepare(); |
81 | |
82 | return ret; |
83 | } |
84 | |
85 | void pxa_pm_finish(void) |
86 | { |
87 | if (pxa_cpu_pm_fns && pxa_cpu_pm_fns->finish) |
88 | pxa_cpu_pm_fns->finish(); |
89 | } |
90 | |
91 | static const struct platform_suspend_ops pxa_pm_ops = { |
92 | .valid = pxa_pm_valid, |
93 | .enter = pxa_pm_enter, |
94 | .prepare = pxa_pm_prepare, |
95 | .finish = pxa_pm_finish, |
96 | }; |
97 | |
98 | static int __init pxa_pm_init(void) |
99 | { |
100 | if (!pxa_cpu_pm_fns) { |
101 | printk(KERN_ERR "no valid pxa_cpu_pm_fns defined\n" ); |
102 | return -EINVAL; |
103 | } |
104 | |
105 | sleep_save = kmalloc_array(n: pxa_cpu_pm_fns->save_count, |
106 | size: sizeof(*sleep_save), |
107 | GFP_KERNEL); |
108 | if (!sleep_save) |
109 | return -ENOMEM; |
110 | |
111 | suspend_set_ops(ops: &pxa_pm_ops); |
112 | return 0; |
113 | } |
114 | |
115 | device_initcall(pxa_pm_init); |
116 | |