1/*
2 * PowerNV OPAL power control for graceful shutdown handling
3 *
4 * Copyright 2015 IBM Corp.
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#include <linux/kernel.h>
13#include <linux/reboot.h>
14#include <linux/notifier.h>
15
16#include <asm/opal.h>
17#include <asm/machdep.h>
18
19#define SOFT_OFF 0x00
20#define SOFT_REBOOT 0x01
21
22static int opal_power_control_event(struct notifier_block *nb,
23				    unsigned long msg_type, void *msg)
24{
25	struct opal_msg *power_msg = msg;
26	uint64_t type;
27
28	type = be64_to_cpu(power_msg->params[0]);
29
30	switch (type) {
31	case SOFT_REBOOT:
32		pr_info("OPAL: reboot requested\n");
33		orderly_reboot();
34		break;
35	case SOFT_OFF:
36		pr_info("OPAL: poweroff requested\n");
37		orderly_poweroff(true);
38		break;
39	default:
40		pr_err("OPAL: power control type unexpected %016llx\n", type);
41	}
42
43	return 0;
44}
45
46static struct notifier_block opal_power_control_nb = {
47	.notifier_call	= opal_power_control_event,
48	.next		= NULL,
49	.priority	= 0,
50};
51
52static int __init opal_power_control_init(void)
53{
54	int ret;
55
56	ret = opal_message_notifier_register(OPAL_MSG_SHUTDOWN,
57					     &opal_power_control_nb);
58	if (ret) {
59		pr_err("%s: Can't register OPAL event notifier (%d)\n",
60				__func__, ret);
61		return ret;
62	}
63
64	return 0;
65}
66machine_subsys_initcall(powernv, opal_power_control_init);
67