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/cdefs.h>
29__FBSDID("$FreeBSD$");
30
31#include <sys/param.h>
32#include <sys/kernel.h>
33#include <sys/bus.h>
34#include <sys/eventhandler.h>
35#include <sys/module.h>
36#include <sys/rman.h>
37#include <sys/systm.h>
38#include <sys/watchdog.h>
39
40#include <dev/superio/superio.h>
41
42#include <machine/bus.h>
43#include <machine/resource.h>
44
45struct ftwd_softc {
46	eventhandler_tag	wd_ev;
47};
48
49static void
50ftwd_func(void *priv, u_int cmd, int *error)
51{
52	device_t dev = priv;
53	uint64_t timeout;
54	uint8_t val = 0;
55	uint8_t minutes = 0;
56
57	if (cmd != 0) {
58		cmd &= WD_INTERVAL;
59
60		/* Convert the requested timeout to seconds. */
61		if (cmd >= WD_TO_1SEC)
62			timeout = (uint64_t)1 << (cmd - WD_TO_1SEC);
63		else
64			timeout = 1;
65
66		if (timeout <= UINT8_MAX) {
67			val = timeout;
68			*error = 0;
69		} else if ((timeout / 60) <= UINT8_MAX) {
70			val = timeout / 60;
71			minutes = 1;
72			*error = 0;
73		}
74	}
75	if (bootverbose) {
76                if (val == 0) {
77			device_printf(dev, "disabling watchdog\n");
78		} else {
79			device_printf(dev,
80			    "arm watchdog to %d %s%s (Was: 0x%02x)\n",
81			    val, minutes ? "minute" : "second",
82                            val == 1 ? "" : "s",
83			    superio_read(dev, 0xf6)
84			);
85		}
86	}
87	superio_write(dev, 0xf0, 0x00);		// Disable WDTRST#
88	superio_write(dev, 0xf6, val);		// Set Counter
89
90	if (minutes)
91		superio_write(dev, 0xf5, 0x7d);	// minutes, act high, 125ms
92	else
93		superio_write(dev, 0xf5, 0x75);	// seconds, act high, 125ms
94
95	if (val)
96		superio_write(dev, 0xf7, 0x01);	// Disable PME
97	if (val)
98		superio_write(dev, 0xf0, 0x81);	// Enable WDTRST#
99	else
100		superio_write(dev, 0xf0, 0x00);	// Disable WDTRST
101}
102
103static int
104ftwd_probe(device_t dev)
105{
106
107	if (superio_vendor(dev) != SUPERIO_VENDOR_FINTEK ||
108	    superio_get_type(dev) != SUPERIO_DEV_WDT)
109		return (ENXIO);
110	device_set_desc(dev, "Watchdog Timer on Fintek SuperIO");
111	return (BUS_PROBE_DEFAULT);
112}
113
114static int
115ftwd_attach(device_t dev)
116{
117	struct ftwd_softc *sc = device_get_softc(dev);
118
119	/*
120	 * We do not touch the watchdog at this time, it might be armed
121	 * by firmware to protect the full boot sequence.
122	 */
123
124	sc->wd_ev = EVENTHANDLER_REGISTER(watchdog_list, ftwd_func, dev, 0);
125	return (0);
126}
127
128static int
129ftwd_detach(device_t dev)
130{
131	struct ftwd_softc *sc = device_get_softc(dev);
132	int dummy;
133
134	if (sc->wd_ev != NULL)
135		EVENTHANDLER_DEREGISTER(watchdog_list, sc->wd_ev);
136	ftwd_func(dev, 0, &dummy);
137	return (0);
138}
139
140static device_method_t ftwd_methods[] = {
141	DEVMETHOD(device_probe,		ftwd_probe),
142	DEVMETHOD(device_attach,	ftwd_attach),
143	DEVMETHOD(device_detach,	ftwd_detach),
144	{ 0, 0 }
145};
146
147static driver_t ftwd_driver = {
148	"ftwd",
149	ftwd_methods,
150	sizeof (struct ftwd_softc)
151};
152
153static devclass_t ftwd_devclass;
154
155DRIVER_MODULE(ftwd, superio, ftwd_driver, ftwd_devclass, NULL, NULL);
156MODULE_DEPEND(ftwd, superio, 1, 1, 1);
157MODULE_VERSION(ftwd, 1);
158