aboutsummaryrefslogtreecommitdiff
path: root/drivers/power/reset/arm-versatile-reboot.c
blob: 08d0a07b58ef284a6b9df6c9d54ad5bdf2ef8988 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2014 Linaro Ltd.
 *
 * Author: Linus Walleij <linus.walleij@linaro.org>
 */
#include <linux/init.h>
#include <linux/mfd/syscon.h>
#include <linux/reboot.h>
#include <linux/regmap.h>
#include <linux/of.h>

#define INTEGRATOR_HDR_CTRL_OFFSET	0x0C
#define INTEGRATOR_HDR_LOCK_OFFSET	0x14
#define INTEGRATOR_CM_CTRL_RESET	(1 << 3)

#define VERSATILE_SYS_LOCK_OFFSET	0x20
#define VERSATILE_SYS_RESETCTL_OFFSET	0x40

/* Magic unlocking token used on all Versatile boards */
#define VERSATILE_LOCK_VAL		0xA05F

/*
 * We detect the different syscon types from the compatible strings.
 */
enum versatile_reboot {
	INTEGRATOR_REBOOT_CM,
	VERSATILE_REBOOT_CM,
	REALVIEW_REBOOT_EB,
	REALVIEW_REBOOT_PB1176,
	REALVIEW_REBOOT_PB11MP,
	REALVIEW_REBOOT_PBA8,
	REALVIEW_REBOOT_PBX,
};

/* Pointer to the system controller */
static struct regmap *syscon_regmap;
static enum versatile_reboot versatile_reboot_type;

static const struct of_device_id versatile_reboot_of_match[] = {
	{
		.compatible = "arm,core-module-integrator",
		.data = (void *)INTEGRATOR_REBOOT_CM
	},
	{
		.compatible = "arm,core-module-versatile",
		.data = (void *)VERSATILE_REBOOT_CM,
	},
	{
		.compatible = "arm,realview-eb-syscon",
		.data = (void *)REALVIEW_REBOOT_EB,
	},
	{
		.compatible = "arm,realview-pb1176-syscon",
		.data = (void *)REALVIEW_REBOOT_PB1176,
	},
	{
		.compatible = "arm,realview-pb11mp-syscon",
		.data = (void *)REALVIEW_REBOOT_PB11MP,
	},
	{
		.compatible = "arm,realview-pba8-syscon",
		.data = (void *)REALVIEW_REBOOT_PBA8,
	},
	{
		.compatible = "arm,realview-pbx-syscon",
		.data = (void *)REALVIEW_REBOOT_PBX,
	},
	{},
};

static int versatile_reboot(struct notifier_block *this, unsigned long mode,
			    void *cmd)
{
	/* Unlock the reset register */
	/* Then hit reset on the different machines */
	switch (versatile_reboot_type) {
	case INTEGRATOR_REBOOT_CM:
		regmap_write(syscon_regmap, INTEGRATOR_HDR_LOCK_OFFSET,
			     VERSATILE_LOCK_VAL);
		regmap_update_bits(syscon_regmap,
				   INTEGRATOR_HDR_CTRL_OFFSET,
				   INTEGRATOR_CM_CTRL_RESET,
				   INTEGRATOR_CM_CTRL_RESET);
		break;
	case VERSATILE_REBOOT_CM:
		regmap_write(syscon_regmap, VERSATILE_SYS_LOCK_OFFSET,
			     VERSATILE_LOCK_VAL);
		regmap_update_bits(syscon_regmap,
				   VERSATILE_SYS_RESETCTL_OFFSET,
				   0x0107,
				   0x0105);
		regmap_write(syscon_regmap, VERSATILE_SYS_LOCK_OFFSET,
			     0);
		break;
	case REALVIEW_REBOOT_EB:
		regmap_write(syscon_regmap, VERSATILE_SYS_LOCK_OFFSET,
			     VERSATILE_LOCK_VAL);
		regmap_write(syscon_regmap,
			     VERSATILE_SYS_RESETCTL_OFFSET, 0x0008);
		break;
	case REALVIEW_REBOOT_PB1176:
		regmap_write(syscon_regmap, VERSATILE_SYS_LOCK_OFFSET,
			     VERSATILE_LOCK_VAL);
		regmap_write(syscon_regmap,
			     VERSATILE_SYS_RESETCTL_OFFSET, 0x0100);
		break;
	case REALVIEW_REBOOT_PB11MP:
	case REALVIEW_REBOOT_PBA8:
		regmap_write(syscon_regmap, VERSATILE_SYS_LOCK_OFFSET,
			     VERSATILE_LOCK_VAL);
		regmap_write(syscon_regmap, VERSATILE_SYS_RESETCTL_OFFSET,
			     0x0000);
		regmap_write(syscon_regmap, VERSATILE_SYS_RESETCTL_OFFSET,
			     0x0004);
		break;
	case REALVIEW_REBOOT_PBX:
		regmap_write(syscon_regmap, VERSATILE_SYS_LOCK_OFFSET,
			     VERSATILE_LOCK_VAL);
		regmap_write(syscon_regmap, VERSATILE_SYS_RESETCTL_OFFSET,
			     0x00f0);
		regmap_write(syscon_regmap, VERSATILE_SYS_RESETCTL_OFFSET,
			     0x00f4);
		break;
	}
	dsb();

	return NOTIFY_DONE;
}

static struct notifier_block versatile_reboot_nb = {
	.notifier_call = versatile_reboot,
	.priority = 192,
};

static int __init versatile_reboot_probe(void)
{
	const struct of_device_id *reboot_id;
	struct device_node *np;
	int err;

	np = of_find_matching_node_and_match(NULL, versatile_reboot_of_match,
						 &reboot_id);
	if (!np)
		return -ENODEV;
	versatile_reboot_type = (enum versatile_reboot)reboot_id->data;

	syscon_regmap = syscon_node_to_regmap(np);
	if (IS_ERR(syscon_regmap))
		return PTR_ERR(syscon_regmap);

	err = register_restart_handler(&versatile_reboot_nb);
	if (err)
		return err;

	pr_info("versatile reboot driver registered\n");
	return 0;
}
device_initcall(versatile_reboot_probe);