1 /*-
2 * Copyright (c) 2006 Sam Leffler. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
18 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
19 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
20 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
22 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 */
24 #include <sys/cdefs.h>
25 __FBSDID("$FreeBSD$");
26
27 /*
28 * IXP4XX Watchdog Timer Support.
29 */
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/module.h>
34 #include <sys/time.h>
35 #include <sys/bus.h>
36 #include <sys/resource.h>
37 #include <sys/rman.h>
38 #include <sys/watchdog.h>
39
40 #include <machine/bus.h>
41 #include <machine/cpu.h>
42 #include <machine/cpufunc.h>
43 #include <machine/resource.h>
44 #include <machine/intr.h>
45
46 #include <arm/xscale/ixp425/ixp425reg.h>
47 #include <arm/xscale/ixp425/ixp425var.h>
48
49 struct ixpwdog_softc {
50 device_t sc_dev;
51 };
52
53 static __inline uint32_t
RD4(struct ixpwdog_softc * sc,bus_size_t off)54 RD4(struct ixpwdog_softc *sc, bus_size_t off)
55 {
56 return bus_space_read_4(&ixp425_bs_tag, IXP425_TIMER_VBASE, off);
57 }
58
59 static __inline void
WR4(struct ixpwdog_softc * sc,bus_size_t off,uint32_t val)60 WR4(struct ixpwdog_softc *sc, bus_size_t off, uint32_t val)
61 {
62 bus_space_write_4(&ixp425_bs_tag, IXP425_TIMER_VBASE, off, val);
63 }
64
65 static void
ixp425_watchdog(void * arg,u_int cmd,int * error)66 ixp425_watchdog(void *arg, u_int cmd, int *error)
67 {
68 struct ixpwdog_softc *sc = arg;
69 u_int u = cmd & WD_INTERVAL;
70
71 WR4(sc, IXP425_OST_WDOG_KEY, OST_WDOG_KEY_MAJICK);
72 if (4 <= u && u <= 35) {
73 WR4(sc, IXP425_OST_WDOG_ENAB, 0);
74 /* approximate 66.66MHz cycles */
75 WR4(sc, IXP425_OST_WDOG, 2<<(u - 4));
76 /* NB: reset on timer expiration */
77 WR4(sc, IXP425_OST_WDOG_ENAB,
78 OST_WDOG_ENAB_CNT_ENA | OST_WDOG_ENAB_RST_ENA);
79 *error = 0;
80 } else {
81 /* disable watchdog */
82 WR4(sc, IXP425_OST_WDOG_ENAB, 0);
83 }
84 WR4(sc, IXP425_OST_WDOG_KEY, 0);
85 }
86
87 static int
ixpwdog_probe(device_t dev)88 ixpwdog_probe(device_t dev)
89 {
90 device_set_desc(dev, "IXP4XX Watchdog Timer");
91 return (0);
92 }
93
94 static int
ixpwdog_attach(device_t dev)95 ixpwdog_attach(device_t dev)
96 {
97 struct ixpwdog_softc *sc = device_get_softc(dev);
98
99 sc->sc_dev = dev;
100
101 EVENTHANDLER_REGISTER(watchdog_list, ixp425_watchdog, sc, 0);
102 return (0);
103 }
104
105 static device_method_t ixpwdog_methods[] = {
106 DEVMETHOD(device_probe, ixpwdog_probe),
107 DEVMETHOD(device_attach, ixpwdog_attach),
108 {0, 0},
109 };
110
111 static driver_t ixpwdog_driver = {
112 "ixpwdog",
113 ixpwdog_methods,
114 sizeof(struct ixpwdog_softc),
115 };
116 static devclass_t ixpwdog_devclass;
117 DRIVER_MODULE(ixpwdog, ixp, ixpwdog_driver, ixpwdog_devclass, 0, 0);
118