1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * linux/arch/unicore32/kernel/pm.c
4 *
5 * Code specific to PKUnity SoC and UniCore ISA
6 *
7 * Maintained by GUAN Xue-tao <gxt@mprc.pku.edu.cn>
8 * Copyright (C) 2001-2010 Guan Xuetao
9 */
10 #include <linux/init.h>
11 #include <linux/module.h>
12 #include <linux/suspend.h>
13 #include <linux/errno.h>
14 #include <linux/slab.h>
15 #include <linux/io.h>
16
17 #include <mach/hardware.h>
18 #include <mach/pm.h>
19
20 #include "setup.h"
21
22 struct puv3_cpu_pm_fns *puv3_cpu_pm_fns;
23 static unsigned long *sleep_save;
24
puv3_pm_enter(suspend_state_t state)25 int puv3_pm_enter(suspend_state_t state)
26 {
27 unsigned long sleep_save_checksum = 0, checksum = 0;
28 int i;
29
30 /* skip registers saving for standby */
31 if (state != PM_SUSPEND_STANDBY) {
32 puv3_cpu_pm_fns->save(sleep_save);
33 /* before sleeping, calculate and save a checksum */
34 for (i = 0; i < puv3_cpu_pm_fns->save_count - 1; i++)
35 sleep_save_checksum += sleep_save[i];
36 }
37
38 /* *** go zzz *** */
39 puv3_cpu_pm_fns->enter(state);
40 cpu_init();
41 #ifdef CONFIG_INPUT_KEYBOARD
42 puv3_ps2_init();
43 #endif
44 #ifdef CONFIG_PCI
45 pci_puv3_preinit();
46 #endif
47 if (state != PM_SUSPEND_STANDBY) {
48 /* after sleeping, validate the checksum */
49 for (i = 0; i < puv3_cpu_pm_fns->save_count - 1; i++)
50 checksum += sleep_save[i];
51
52 /* if invalid, display message and wait for a hardware reset */
53 if (checksum != sleep_save_checksum) {
54 while (1)
55 puv3_cpu_pm_fns->enter(state);
56 }
57 puv3_cpu_pm_fns->restore(sleep_save);
58 }
59
60 pr_debug("*** made it back from resume\n");
61
62 return 0;
63 }
64 EXPORT_SYMBOL_GPL(puv3_pm_enter);
65
sleep_phys_sp(void * sp)66 unsigned long sleep_phys_sp(void *sp)
67 {
68 return virt_to_phys(sp);
69 }
70
puv3_pm_valid(suspend_state_t state)71 static int puv3_pm_valid(suspend_state_t state)
72 {
73 if (puv3_cpu_pm_fns)
74 return puv3_cpu_pm_fns->valid(state);
75
76 return -EINVAL;
77 }
78
puv3_pm_prepare(void)79 static int puv3_pm_prepare(void)
80 {
81 int ret = 0;
82
83 if (puv3_cpu_pm_fns && puv3_cpu_pm_fns->prepare)
84 ret = puv3_cpu_pm_fns->prepare();
85
86 return ret;
87 }
88
puv3_pm_finish(void)89 static void puv3_pm_finish(void)
90 {
91 if (puv3_cpu_pm_fns && puv3_cpu_pm_fns->finish)
92 puv3_cpu_pm_fns->finish();
93 }
94
95 static struct platform_suspend_ops puv3_pm_ops = {
96 .valid = puv3_pm_valid,
97 .enter = puv3_pm_enter,
98 .prepare = puv3_pm_prepare,
99 .finish = puv3_pm_finish,
100 };
101
puv3_pm_init(void)102 static int __init puv3_pm_init(void)
103 {
104 if (!puv3_cpu_pm_fns) {
105 printk(KERN_ERR "no valid puv3_cpu_pm_fns defined\n");
106 return -EINVAL;
107 }
108
109 sleep_save = kmalloc_array(puv3_cpu_pm_fns->save_count,
110 sizeof(unsigned long),
111 GFP_KERNEL);
112 if (!sleep_save) {
113 printk(KERN_ERR "failed to alloc memory for pm save\n");
114 return -ENOMEM;
115 }
116
117 suspend_set_ops(&puv3_pm_ops);
118 return 0;
119 }
120
121 device_initcall(puv3_pm_init);
122
