1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2020 Poul-Henning Kamp
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28#include <sys/param.h>
29#include <sys/kernel.h>
30#include <sys/bus.h>
31#include <sys/eventhandler.h>
32#include <sys/module.h>
33#include <sys/rman.h>
34#include <sys/systm.h>
35#include <sys/watchdog.h>
36
37#include <dev/superio/superio.h>
38
39#include <machine/bus.h>
40#include <machine/resource.h>
41
42struct ftwd_softc {
43	eventhandler_tag	wd_ev;
44};
45
46static void
47ftwd_func(void *priv, u_int cmd, int *error)
48{
49	device_t dev = priv;
50	uint64_t timeout;
51	uint8_t val = 0;
52	uint8_t minutes = 0;
53
54	if (cmd != 0) {
55		cmd &= WD_INTERVAL;
56
57		/* Convert the requested timeout to seconds. */
58		if (cmd >= WD_TO_1SEC)
59			timeout = (uint64_t)1 << (cmd - WD_TO_1SEC);
60		else
61			timeout = 1;
62
63		if (timeout <= UINT8_MAX) {
64			val = timeout;
65			*error = 0;
66		} else if ((timeout / 60) <= UINT8_MAX) {
67			val = timeout / 60;
68			minutes = 1;
69			*error = 0;
70		}
71	}
72	if (bootverbose) {
73                if (val == 0) {
74			device_printf(dev, "disabling watchdog\n");
75		} else {
76			device_printf(dev,
77			    "arm watchdog to %d %s%s (Was: 0x%02x)\n",
78			    val, minutes ? "minute" : "second",
79                            val == 1 ? "" : "s",
80			    superio_read(dev, 0xf6)
81			);
82		}
83	}
84	superio_write(dev, 0xf0, 0x00);		// Disable WDTRST#
85	superio_write(dev, 0xf6, val);		// Set Counter
86
87	if (minutes)
88		superio_write(dev, 0xf5, 0x7d);	// minutes, act high, 125ms
89	else
90		superio_write(dev, 0xf5, 0x75);	// seconds, act high, 125ms
91
92	if (val)
93		superio_write(dev, 0xf7, 0x01);	// Disable PME
94	if (val)
95		superio_write(dev, 0xf0, 0x81);	// Enable WDTRST#
96	else
97		superio_write(dev, 0xf0, 0x00);	// Disable WDTRST
98}
99
100static int
101ftwd_probe(device_t dev)
102{
103
104	if (superio_vendor(dev) != SUPERIO_VENDOR_FINTEK ||
105	    superio_get_type(dev) != SUPERIO_DEV_WDT)
106		return (ENXIO);
107	device_set_desc(dev, "Watchdog Timer on Fintek SuperIO");
108	return (BUS_PROBE_DEFAULT);
109}
110
111static int
112ftwd_attach(device_t dev)
113{
114	struct ftwd_softc *sc = device_get_softc(dev);
115
116	/*
117	 * We do not touch the watchdog at this time, it might be armed
118	 * by firmware to protect the full boot sequence.
119	 */
120
121	sc->wd_ev = EVENTHANDLER_REGISTER(watchdog_list, ftwd_func, dev, 0);
122	return (0);
123}
124
125static int
126ftwd_detach(device_t dev)
127{
128	struct ftwd_softc *sc = device_get_softc(dev);
129	int dummy;
130
131	if (sc->wd_ev != NULL)
132		EVENTHANDLER_DEREGISTER(watchdog_list, sc->wd_ev);
133	ftwd_func(dev, 0, &dummy);
134	return (0);
135}
136
137static device_method_t ftwd_methods[] = {
138	DEVMETHOD(device_probe,		ftwd_probe),
139	DEVMETHOD(device_attach,	ftwd_attach),
140	DEVMETHOD(device_detach,	ftwd_detach),
141	{ 0, 0 }
142};
143
144static driver_t ftwd_driver = {
145	"ftwd",
146	ftwd_methods,
147	sizeof (struct ftwd_softc)
148};
149
150DRIVER_MODULE(ftwd, superio, ftwd_driver, NULL, NULL);
151MODULE_DEPEND(ftwd, superio, 1, 1, 1);
152MODULE_VERSION(ftwd, 1);
153