1// SPDX-License-Identifier: GPL-2.0
 2/*
 3 * Renesas R-Mobile Reset Driver
 4 *
 5 * Copyright (C) 2014 Glider bvba
 6 */
 7
 8#include <linux/io.h>
 9#include <linux/module.h>
10#include <linux/notifier.h>
11#include <linux/of_address.h>
12#include <linux/platform_device.h>
13#include <linux/printk.h>
14#include <linux/reboot.h>
15
16/* SYSC Register Bank 2 */
17#define RESCNT2		0x20		/* Reset Control Register 2 */
18
19/* Reset Control Register 2 */
20#define RESCNT2_PRES	0x80000000	/* Soft power-on reset */
21
22static void __iomem *sysc_base2;
23
24static int rmobile_reset_handler(struct notifier_block *this,
25				 unsigned long mode, void *cmd)
26{
27	pr_debug("%s %lu\n", __func__, mode);
28
29	/* Let's assume we have acquired the HPB semaphore */
30	writel(RESCNT2_PRES, sysc_base2 + RESCNT2);
31
32	return NOTIFY_DONE;
33}
34
35static struct notifier_block rmobile_reset_nb = {
36	.notifier_call = rmobile_reset_handler,
37	.priority = 192,
38};
39
40static int rmobile_reset_probe(struct platform_device *pdev)
41{
42	int error;
43
44	sysc_base2 = of_iomap(pdev->dev.of_node, 1);
45	if (!sysc_base2)
46		return -ENODEV;
47
48	error = register_restart_handler(&rmobile_reset_nb);
49	if (error) {
50		dev_err(&pdev->dev,
51			"cannot register restart handler (err=%d)\n", error);
52		goto fail_unmap;
53	}
54
55	return 0;
56
57fail_unmap:
58	iounmap(sysc_base2);
59	return error;
60}
61
62static void rmobile_reset_remove(struct platform_device *pdev)
63{
64	unregister_restart_handler(&rmobile_reset_nb);
65	iounmap(sysc_base2);
 
66}
67
68static const struct of_device_id rmobile_reset_of_match[] = {
69	{ .compatible = "renesas,sysc-rmobile", },
70	{ /* sentinel */ }
71};
72MODULE_DEVICE_TABLE(of, rmobile_reset_of_match);
73
74static struct platform_driver rmobile_reset_driver = {
75	.probe = rmobile_reset_probe,
76	.remove_new = rmobile_reset_remove,
77	.driver = {
78		.name = "rmobile_reset",
79		.of_match_table = rmobile_reset_of_match,
80	},
81};
82
83module_platform_driver(rmobile_reset_driver);
84
85MODULE_DESCRIPTION("Renesas R-Mobile Reset Driver");
86MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>");
87MODULE_LICENSE("GPL v2");

 1// SPDX-License-Identifier: GPL-2.0
 2/*
 3 * Renesas R-Mobile Reset Driver
 4 *
 5 * Copyright (C) 2014 Glider bvba
 6 */
 7
 8#include <linux/io.h>
 9#include <linux/module.h>
10#include <linux/notifier.h>
11#include <linux/of_address.h>
12#include <linux/platform_device.h>
13#include <linux/printk.h>
14#include <linux/reboot.h>
15
16/* SYSC Register Bank 2 */
17#define RESCNT2		0x20		/* Reset Control Register 2 */
18
19/* Reset Control Register 2 */
20#define RESCNT2_PRES	0x80000000	/* Soft power-on reset */
21
22static void __iomem *sysc_base2;
23
24static int rmobile_reset_handler(struct notifier_block *this,
25				 unsigned long mode, void *cmd)
26{
27	pr_debug("%s %lu\n", __func__, mode);
28
29	/* Let's assume we have acquired the HPB semaphore */
30	writel(RESCNT2_PRES, sysc_base2 + RESCNT2);
31
32	return NOTIFY_DONE;
33}
34
35static struct notifier_block rmobile_reset_nb = {
36	.notifier_call = rmobile_reset_handler,
37	.priority = 192,
38};
39
40static int rmobile_reset_probe(struct platform_device *pdev)
41{
42	int error;
43
44	sysc_base2 = of_iomap(pdev->dev.of_node, 1);
45	if (!sysc_base2)
46		return -ENODEV;
47
48	error = register_restart_handler(&rmobile_reset_nb);
49	if (error) {
50		dev_err(&pdev->dev,
51			"cannot register restart handler (err=%d)\n", error);
52		goto fail_unmap;
53	}
54
55	return 0;
56
57fail_unmap:
58	iounmap(sysc_base2);
59	return error;
60}
61
62static int rmobile_reset_remove(struct platform_device *pdev)
63{
64	unregister_restart_handler(&rmobile_reset_nb);
65	iounmap(sysc_base2);
66	return 0;
67}
68
69static const struct of_device_id rmobile_reset_of_match[] = {
70	{ .compatible = "renesas,sysc-rmobile", },
71	{ /* sentinel */ }
72};
73MODULE_DEVICE_TABLE(of, rmobile_reset_of_match);
74
75static struct platform_driver rmobile_reset_driver = {
76	.probe = rmobile_reset_probe,
77	.remove = rmobile_reset_remove,
78	.driver = {
79		.name = "rmobile_reset",
80		.of_match_table = rmobile_reset_of_match,
81	},
82};
83
84module_platform_driver(rmobile_reset_driver);
85
86MODULE_DESCRIPTION("Renesas R-Mobile Reset Driver");
87MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>");
88MODULE_LICENSE("GPL v2");