1/*
2 * ZTE zx296702 SoC reset code
3 *
4 * Copyright (c) 2015 Linaro Ltd.
5 *
6 * Author: Jun Nie <jun.nie@linaro.org>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13#include <linux/delay.h>
14#include <linux/io.h>
15#include <linux/module.h>
16#include <linux/notifier.h>
17#include <linux/of_address.h>
18#include <linux/platform_device.h>
19#include <linux/reboot.h>
20
21static void __iomem *base;
22static void __iomem *pcu_base;
23
24static int zx_restart_handler(struct notifier_block *this,
25			      unsigned long mode, void *cmd)
26{
27	writel_relaxed(1, base + 0xb0);
28	writel_relaxed(1, pcu_base + 0x34);
29
30	mdelay(50);
31	pr_emerg("Unable to restart system\n");
32
33	return NOTIFY_DONE;
34}
35
36static struct notifier_block zx_restart_nb = {
37	.notifier_call = zx_restart_handler,
38	.priority = 128,
39};
40
41static int zx_reboot_probe(struct platform_device *pdev)
42{
43	struct device_node *np = pdev->dev.of_node;
44	int err;
45
46	base = of_iomap(np, 0);
47	if (!base) {
48		WARN(1, "failed to map base address");
49		return -ENODEV;
50	}
51
52	np = of_find_compatible_node(NULL, NULL, "zte,zx296702-pcu");
53	pcu_base = of_iomap(np, 0);
54	if (!pcu_base) {
55		iounmap(base);
56		WARN(1, "failed to map pcu_base address");
57		return -ENODEV;
58	}
59
60	err = register_restart_handler(&zx_restart_nb);
61	if (err)
62		dev_err(&pdev->dev, "Register restart handler failed(err=%d)\n",
63			err);
64
65	return err;
66}
67
68static const struct of_device_id zx_reboot_of_match[] = {
69	{ .compatible = "zte,sysctrl" },
70	{}
71};
72
73static struct platform_driver zx_reboot_driver = {
74	.probe = zx_reboot_probe,
75	.driver = {
76		.name = "zx-reboot",
77		.of_match_table = zx_reboot_of_match,
78	},
79};
80module_platform_driver(zx_reboot_driver);
81