xref: /freebsd/sys/dev/ftwd/ftwd.c (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
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 #include <sys/param.h>
30 #include <sys/kernel.h>
31 #include <sys/bus.h>
32 #include <sys/eventhandler.h>
33 #include <sys/module.h>
34 #include <sys/rman.h>
35 #include <sys/systm.h>
36 #include <sys/watchdog.h>
37 
38 #include <dev/superio/superio.h>
39 
40 #include <machine/bus.h>
41 #include <machine/resource.h>
42 
43 struct ftwd_softc {
44 	eventhandler_tag	wd_ev;
45 };
46 
47 static void
48 ftwd_func(void *priv, u_int cmd, int *error)
49 {
50 	device_t dev = priv;
51 	uint64_t timeout;
52 	uint8_t val = 0;
53 	uint8_t minutes = 0;
54 
55 	if (cmd != 0) {
56 		cmd &= WD_INTERVAL;
57 
58 		/* Convert the requested timeout to seconds. */
59 		if (cmd >= WD_TO_1SEC)
60 			timeout = (uint64_t)1 << (cmd - WD_TO_1SEC);
61 		else
62 			timeout = 1;
63 
64 		if (timeout <= UINT8_MAX) {
65 			val = timeout;
66 			*error = 0;
67 		} else if ((timeout / 60) <= UINT8_MAX) {
68 			val = timeout / 60;
69 			minutes = 1;
70 			*error = 0;
71 		}
72 	}
73 	if (bootverbose) {
74                 if (val == 0) {
75 			device_printf(dev, "disabling watchdog\n");
76 		} else {
77 			device_printf(dev,
78 			    "arm watchdog to %d %s%s (Was: 0x%02x)\n",
79 			    val, minutes ? "minute" : "second",
80                             val == 1 ? "" : "s",
81 			    superio_read(dev, 0xf6)
82 			);
83 		}
84 	}
85 	superio_write(dev, 0xf0, 0x00);		// Disable WDTRST#
86 	superio_write(dev, 0xf6, val);		// Set Counter
87 
88 	if (minutes)
89 		superio_write(dev, 0xf5, 0x7d);	// minutes, act high, 125ms
90 	else
91 		superio_write(dev, 0xf5, 0x75);	// seconds, act high, 125ms
92 
93 	if (val)
94 		superio_write(dev, 0xf7, 0x01);	// Disable PME
95 	if (val)
96 		superio_write(dev, 0xf0, 0x81);	// Enable WDTRST#
97 	else
98 		superio_write(dev, 0xf0, 0x00);	// Disable WDTRST
99 }
100 
101 static int
102 ftwd_probe(device_t dev)
103 {
104 
105 	if (superio_vendor(dev) != SUPERIO_VENDOR_FINTEK ||
106 	    superio_get_type(dev) != SUPERIO_DEV_WDT)
107 		return (ENXIO);
108 	device_set_desc(dev, "Watchdog Timer on Fintek SuperIO");
109 	return (BUS_PROBE_DEFAULT);
110 }
111 
112 static int
113 ftwd_attach(device_t dev)
114 {
115 	struct ftwd_softc *sc = device_get_softc(dev);
116 
117 	/*
118 	 * We do not touch the watchdog at this time, it might be armed
119 	 * by firmware to protect the full boot sequence.
120 	 */
121 
122 	sc->wd_ev = EVENTHANDLER_REGISTER(watchdog_list, ftwd_func, dev, 0);
123 	return (0);
124 }
125 
126 static int
127 ftwd_detach(device_t dev)
128 {
129 	struct ftwd_softc *sc = device_get_softc(dev);
130 	int dummy;
131 
132 	if (sc->wd_ev != NULL)
133 		EVENTHANDLER_DEREGISTER(watchdog_list, sc->wd_ev);
134 	ftwd_func(dev, 0, &dummy);
135 	return (0);
136 }
137 
138 static device_method_t ftwd_methods[] = {
139 	DEVMETHOD(device_probe,		ftwd_probe),
140 	DEVMETHOD(device_attach,	ftwd_attach),
141 	DEVMETHOD(device_detach,	ftwd_detach),
142 	{ 0, 0 }
143 };
144 
145 static driver_t ftwd_driver = {
146 	"ftwd",
147 	ftwd_methods,
148 	sizeof (struct ftwd_softc)
149 };
150 
151 DRIVER_MODULE(ftwd, superio, ftwd_driver, NULL, NULL);
152 MODULE_DEPEND(ftwd, superio, 1, 1, 1);
153 MODULE_VERSION(ftwd, 1);
154