1/*
2 * Copyright (C) 2013 Broadcom Corporation
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation version 2.
7 *
8 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
9 * kind, whether express or implied; without even the implied warranty
10 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11 * GNU General Public License for more details.
12 */
13
14#include <linux/device.h>
15#include <linux/errno.h>
16#include <linux/init.h>
17#include <linux/io.h>
18#include <linux/jiffies.h>
19#include <linux/of_address.h>
20#include <linux/of_irq.h>
21#include <linux/of_platform.h>
22#include <linux/platform_device.h>
23#include <linux/printk.h>
24#include <linux/reboot.h>
25#include <linux/regmap.h>
26#include <linux/smp.h>
27#include <linux/mfd/syscon.h>
28
29#include <asm/system_misc.h>
30
31#define RESET_SOURCE_ENABLE_REG 1
32#define SW_MASTER_RESET_REG 2
33
34static struct regmap *regmap;
35static u32 rst_src_en;
36static u32 sw_mstr_rst;
37
38static void brcmstb_reboot(enum reboot_mode mode, const char *cmd)
39{
40	int rc;
41	u32 tmp;
42
43	rc = regmap_write(regmap, rst_src_en, 1);
44	if (rc) {
45		pr_err("failed to write rst_src_en (%d)\n", rc);
46		return;
47	}
48
49	rc = regmap_read(regmap, rst_src_en, &tmp);
50	if (rc) {
51		pr_err("failed to read rst_src_en (%d)\n", rc);
52		return;
53	}
54
55	rc = regmap_write(regmap, sw_mstr_rst, 1);
56	if (rc) {
57		pr_err("failed to write sw_mstr_rst (%d)\n", rc);
58		return;
59	}
60
61	rc = regmap_read(regmap, sw_mstr_rst, &tmp);
62	if (rc) {
63		pr_err("failed to read sw_mstr_rst (%d)\n", rc);
64		return;
65	}
66
67	while (1)
68		;
69}
70
71static int brcmstb_reboot_probe(struct platform_device *pdev)
72{
73	int rc;
74	struct device_node *np = pdev->dev.of_node;
75
76	regmap = syscon_regmap_lookup_by_phandle(np, "syscon");
77	if (IS_ERR(regmap)) {
78		pr_err("failed to get syscon phandle\n");
79		return -EINVAL;
80	}
81
82	rc = of_property_read_u32_index(np, "syscon", RESET_SOURCE_ENABLE_REG,
83					&rst_src_en);
84	if (rc) {
85		pr_err("can't get rst_src_en offset (%d)\n", rc);
86		return -EINVAL;
87	}
88
89	rc = of_property_read_u32_index(np, "syscon", SW_MASTER_RESET_REG,
90					&sw_mstr_rst);
91	if (rc) {
92		pr_err("can't get sw_mstr_rst offset (%d)\n", rc);
93		return -EINVAL;
94	}
95
96	arm_pm_restart = brcmstb_reboot;
97
98	return 0;
99}
100
101static const struct of_device_id of_match[] = {
102	{ .compatible = "brcm,brcmstb-reboot", },
103	{},
104};
105
106static struct platform_driver brcmstb_reboot_driver = {
107	.probe = brcmstb_reboot_probe,
108	.driver = {
109		.name = "brcmstb-reboot",
110		.owner = THIS_MODULE,
111		.of_match_table = of_match,
112	},
113};
114
115static int __init brcmstb_reboot_init(void)
116{
117	return platform_driver_probe(&brcmstb_reboot_driver,
118					brcmstb_reboot_probe);
119}
120subsys_initcall(brcmstb_reboot_init);
121