1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * HiSilicon SoC reset code |
4 | * |
5 | * Copyright (c) 2014 HiSilicon Ltd. |
6 | * Copyright (c) 2014 Linaro Ltd. |
7 | * |
8 | * Author: Haojian Zhuang <haojian.zhuang@linaro.org> |
9 | */ |
10 | |
11 | #include <linux/delay.h> |
12 | #include <linux/io.h> |
13 | #include <linux/module.h> |
14 | #include <linux/notifier.h> |
15 | #include <linux/of_address.h> |
16 | #include <linux/platform_device.h> |
17 | #include <linux/reboot.h> |
18 | |
19 | #include <asm/proc-fns.h> |
20 | |
21 | static void __iomem *base; |
22 | static u32 reboot_offset; |
23 | |
24 | static int hisi_restart_handler(struct notifier_block *this, |
25 | unsigned long mode, void *cmd) |
26 | { |
27 | writel_relaxed(0xdeadbeef, base + reboot_offset); |
28 | |
29 | while (1) |
30 | cpu_do_idle(); |
31 | |
32 | return NOTIFY_DONE; |
33 | } |
34 | |
35 | static struct notifier_block hisi_restart_nb = { |
36 | .notifier_call = hisi_restart_handler, |
37 | .priority = 128, |
38 | }; |
39 | |
40 | static int hisi_reboot_probe(struct platform_device *pdev) |
41 | { |
42 | struct device_node *np = pdev->dev.of_node; |
43 | int err; |
44 | |
45 | base = of_iomap(node: np, index: 0); |
46 | if (!base) { |
47 | WARN(1, "failed to map base address" ); |
48 | return -ENODEV; |
49 | } |
50 | |
51 | if (of_property_read_u32(np, propname: "reboot-offset" , out_value: &reboot_offset) < 0) { |
52 | pr_err("failed to find reboot-offset property\n" ); |
53 | iounmap(addr: base); |
54 | return -EINVAL; |
55 | } |
56 | |
57 | err = register_restart_handler(&hisi_restart_nb); |
58 | if (err) { |
59 | dev_err(&pdev->dev, "cannot register restart handler (err=%d)\n" , |
60 | err); |
61 | iounmap(addr: base); |
62 | } |
63 | |
64 | return err; |
65 | } |
66 | |
67 | static const struct of_device_id hisi_reboot_of_match[] = { |
68 | { .compatible = "hisilicon,sysctrl" }, |
69 | {} |
70 | }; |
71 | MODULE_DEVICE_TABLE(of, hisi_reboot_of_match); |
72 | |
73 | static struct platform_driver hisi_reboot_driver = { |
74 | .probe = hisi_reboot_probe, |
75 | .driver = { |
76 | .name = "hisi-reboot" , |
77 | .of_match_table = hisi_reboot_of_match, |
78 | }, |
79 | }; |
80 | module_platform_driver(hisi_reboot_driver); |
81 | |