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
pxa_pm_enter(suspend_state_t state)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
pxa_pm_valid(suspend_state_t state)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
pxa_pm_prepare(void)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
pxa_pm_finish(void)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
pxa_pm_init(void)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(pxa_cpu_pm_fns->save_count,
106 sizeof(*sleep_save),
107 GFP_KERNEL);
108 if (!sleep_save)
109 return -ENOMEM;
110
111 suspend_set_ops(&pxa_pm_ops);
112 return 0;
113 }
114
115 device_initcall(pxa_pm_init);
116