1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * ZTE zx296702 SoC reset code
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (c) 2015 Linaro Ltd.
6*4882a593Smuzhiyun *
7*4882a593Smuzhiyun * Author: Jun Nie <jun.nie@linaro.org>
8*4882a593Smuzhiyun */
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #include <linux/delay.h>
11*4882a593Smuzhiyun #include <linux/io.h>
12*4882a593Smuzhiyun #include <linux/module.h>
13*4882a593Smuzhiyun #include <linux/notifier.h>
14*4882a593Smuzhiyun #include <linux/of_address.h>
15*4882a593Smuzhiyun #include <linux/platform_device.h>
16*4882a593Smuzhiyun #include <linux/reboot.h>
17*4882a593Smuzhiyun
18*4882a593Smuzhiyun static void __iomem *base;
19*4882a593Smuzhiyun static void __iomem *pcu_base;
20*4882a593Smuzhiyun
zx_restart_handler(struct notifier_block * this,unsigned long mode,void * cmd)21*4882a593Smuzhiyun static int zx_restart_handler(struct notifier_block *this,
22*4882a593Smuzhiyun unsigned long mode, void *cmd)
23*4882a593Smuzhiyun {
24*4882a593Smuzhiyun writel_relaxed(1, base + 0xb0);
25*4882a593Smuzhiyun writel_relaxed(1, pcu_base + 0x34);
26*4882a593Smuzhiyun
27*4882a593Smuzhiyun mdelay(50);
28*4882a593Smuzhiyun pr_emerg("Unable to restart system\n");
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun return NOTIFY_DONE;
31*4882a593Smuzhiyun }
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun static struct notifier_block zx_restart_nb = {
34*4882a593Smuzhiyun .notifier_call = zx_restart_handler,
35*4882a593Smuzhiyun .priority = 128,
36*4882a593Smuzhiyun };
37*4882a593Smuzhiyun
zx_reboot_probe(struct platform_device * pdev)38*4882a593Smuzhiyun static int zx_reboot_probe(struct platform_device *pdev)
39*4882a593Smuzhiyun {
40*4882a593Smuzhiyun struct device_node *np = pdev->dev.of_node;
41*4882a593Smuzhiyun int err;
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun base = of_iomap(np, 0);
44*4882a593Smuzhiyun if (!base) {
45*4882a593Smuzhiyun WARN(1, "failed to map base address");
46*4882a593Smuzhiyun return -ENODEV;
47*4882a593Smuzhiyun }
48*4882a593Smuzhiyun
49*4882a593Smuzhiyun np = of_find_compatible_node(NULL, NULL, "zte,zx296702-pcu");
50*4882a593Smuzhiyun pcu_base = of_iomap(np, 0);
51*4882a593Smuzhiyun of_node_put(np);
52*4882a593Smuzhiyun if (!pcu_base) {
53*4882a593Smuzhiyun iounmap(base);
54*4882a593Smuzhiyun WARN(1, "failed to map pcu_base address");
55*4882a593Smuzhiyun return -ENODEV;
56*4882a593Smuzhiyun }
57*4882a593Smuzhiyun
58*4882a593Smuzhiyun err = register_restart_handler(&zx_restart_nb);
59*4882a593Smuzhiyun if (err) {
60*4882a593Smuzhiyun iounmap(base);
61*4882a593Smuzhiyun iounmap(pcu_base);
62*4882a593Smuzhiyun dev_err(&pdev->dev, "Register restart handler failed(err=%d)\n",
63*4882a593Smuzhiyun err);
64*4882a593Smuzhiyun }
65*4882a593Smuzhiyun
66*4882a593Smuzhiyun return err;
67*4882a593Smuzhiyun }
68*4882a593Smuzhiyun
69*4882a593Smuzhiyun static const struct of_device_id zx_reboot_of_match[] = {
70*4882a593Smuzhiyun { .compatible = "zte,sysctrl" },
71*4882a593Smuzhiyun {}
72*4882a593Smuzhiyun };
73*4882a593Smuzhiyun MODULE_DEVICE_TABLE(of, zx_reboot_of_match);
74*4882a593Smuzhiyun
75*4882a593Smuzhiyun static struct platform_driver zx_reboot_driver = {
76*4882a593Smuzhiyun .probe = zx_reboot_probe,
77*4882a593Smuzhiyun .driver = {
78*4882a593Smuzhiyun .name = "zx-reboot",
79*4882a593Smuzhiyun .of_match_table = zx_reboot_of_match,
80*4882a593Smuzhiyun },
81*4882a593Smuzhiyun };
82*4882a593Smuzhiyun module_platform_driver(zx_reboot_driver);
83*4882a593Smuzhiyun
84*4882a593Smuzhiyun MODULE_DESCRIPTION("ZTE SoCs reset driver");
85*4882a593Smuzhiyun MODULE_AUTHOR("Jun Nie <jun.nie@linaro.org>");
86*4882a593Smuzhiyun MODULE_LICENSE("GPL v2");
87