1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Hisilicon SoC reset code
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (c) 2014 Hisilicon Ltd.
6*4882a593Smuzhiyun * Copyright (c) 2014 Linaro Ltd.
7*4882a593Smuzhiyun *
8*4882a593Smuzhiyun * Author: Haojian Zhuang <haojian.zhuang@linaro.org>
9*4882a593Smuzhiyun */
10*4882a593Smuzhiyun
11*4882a593Smuzhiyun #include <linux/delay.h>
12*4882a593Smuzhiyun #include <linux/io.h>
13*4882a593Smuzhiyun #include <linux/module.h>
14*4882a593Smuzhiyun #include <linux/notifier.h>
15*4882a593Smuzhiyun #include <linux/of_address.h>
16*4882a593Smuzhiyun #include <linux/platform_device.h>
17*4882a593Smuzhiyun #include <linux/reboot.h>
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun #include <asm/proc-fns.h>
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun static void __iomem *base;
22*4882a593Smuzhiyun static u32 reboot_offset;
23*4882a593Smuzhiyun
hisi_restart_handler(struct notifier_block * this,unsigned long mode,void * cmd)24*4882a593Smuzhiyun static int hisi_restart_handler(struct notifier_block *this,
25*4882a593Smuzhiyun unsigned long mode, void *cmd)
26*4882a593Smuzhiyun {
27*4882a593Smuzhiyun writel_relaxed(0xdeadbeef, base + reboot_offset);
28*4882a593Smuzhiyun
29*4882a593Smuzhiyun while (1)
30*4882a593Smuzhiyun cpu_do_idle();
31*4882a593Smuzhiyun
32*4882a593Smuzhiyun return NOTIFY_DONE;
33*4882a593Smuzhiyun }
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun static struct notifier_block hisi_restart_nb = {
36*4882a593Smuzhiyun .notifier_call = hisi_restart_handler,
37*4882a593Smuzhiyun .priority = 128,
38*4882a593Smuzhiyun };
39*4882a593Smuzhiyun
hisi_reboot_probe(struct platform_device * pdev)40*4882a593Smuzhiyun static int hisi_reboot_probe(struct platform_device *pdev)
41*4882a593Smuzhiyun {
42*4882a593Smuzhiyun struct device_node *np = pdev->dev.of_node;
43*4882a593Smuzhiyun int err;
44*4882a593Smuzhiyun
45*4882a593Smuzhiyun base = of_iomap(np, 0);
46*4882a593Smuzhiyun if (!base) {
47*4882a593Smuzhiyun WARN(1, "failed to map base address");
48*4882a593Smuzhiyun return -ENODEV;
49*4882a593Smuzhiyun }
50*4882a593Smuzhiyun
51*4882a593Smuzhiyun if (of_property_read_u32(np, "reboot-offset", &reboot_offset) < 0) {
52*4882a593Smuzhiyun pr_err("failed to find reboot-offset property\n");
53*4882a593Smuzhiyun iounmap(base);
54*4882a593Smuzhiyun return -EINVAL;
55*4882a593Smuzhiyun }
56*4882a593Smuzhiyun
57*4882a593Smuzhiyun err = register_restart_handler(&hisi_restart_nb);
58*4882a593Smuzhiyun if (err) {
59*4882a593Smuzhiyun dev_err(&pdev->dev, "cannot register restart handler (err=%d)\n",
60*4882a593Smuzhiyun err);
61*4882a593Smuzhiyun iounmap(base);
62*4882a593Smuzhiyun }
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun return err;
65*4882a593Smuzhiyun }
66*4882a593Smuzhiyun
67*4882a593Smuzhiyun static const struct of_device_id hisi_reboot_of_match[] = {
68*4882a593Smuzhiyun { .compatible = "hisilicon,sysctrl" },
69*4882a593Smuzhiyun {}
70*4882a593Smuzhiyun };
71*4882a593Smuzhiyun
72*4882a593Smuzhiyun static struct platform_driver hisi_reboot_driver = {
73*4882a593Smuzhiyun .probe = hisi_reboot_probe,
74*4882a593Smuzhiyun .driver = {
75*4882a593Smuzhiyun .name = "hisi-reboot",
76*4882a593Smuzhiyun .of_match_table = hisi_reboot_of_match,
77*4882a593Smuzhiyun },
78*4882a593Smuzhiyun };
79*4882a593Smuzhiyun module_platform_driver(hisi_reboot_driver);
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