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/frame.h>
44#include <machine/resource.h>
45#include <machine/intr.h>
46
47#include <arm/xscale/ixp425/ixp425reg.h>
48#include <arm/xscale/ixp425/ixp425var.h>
49
50struct ixpwdog_softc {
51	device_t		sc_dev;
52};
53
54static __inline uint32_t
55RD4(struct ixpwdog_softc *sc, bus_size_t off)
56{
57	return bus_space_read_4(&ixp425_bs_tag, IXP425_TIMER_VBASE, off);
58}
59
60static __inline void
61WR4(struct ixpwdog_softc *sc, bus_size_t off, uint32_t val)
62{
63	bus_space_write_4(&ixp425_bs_tag, IXP425_TIMER_VBASE, off, val);
64}
65
66static void
67ixp425_watchdog(void *arg, u_int cmd, int *error)
68{
69	struct ixpwdog_softc *sc = arg;
70	u_int u = cmd & WD_INTERVAL;
71
72	WR4(sc, IXP425_OST_WDOG_KEY, OST_WDOG_KEY_MAJICK);
73	if (4 <= u && u <= 35) {
74		WR4(sc, IXP425_OST_WDOG_ENAB, 0);
75		/* approximate 66.66MHz cycles */
76		WR4(sc, IXP425_OST_WDOG, 2<<(u - 4));
77		/* NB: reset on timer expiration */
78		WR4(sc, IXP425_OST_WDOG_ENAB,
79		    OST_WDOG_ENAB_CNT_ENA | OST_WDOG_ENAB_RST_ENA);
80		*error = 0;
81	} else {
82		/* disable watchdog */
83		WR4(sc, IXP425_OST_WDOG_ENAB, 0);
84	}
85	WR4(sc, IXP425_OST_WDOG_KEY, 0);
86}
87
88static int
89ixpwdog_probe(device_t dev)
90{
91	device_set_desc(dev, "IXP4XX Watchdog Timer");
92	return (0);
93}
94
95static int
96ixpwdog_attach(device_t dev)
97{
98	struct ixpwdog_softc *sc = device_get_softc(dev);
99
100	sc->sc_dev = dev;
101
102	EVENTHANDLER_REGISTER(watchdog_list, ixp425_watchdog, sc, 0);
103	return (0);
104}
105
106static device_method_t ixpwdog_methods[] = {
107	DEVMETHOD(device_probe,		ixpwdog_probe),
108	DEVMETHOD(device_attach,	ixpwdog_attach),
109	{0, 0},
110};
111
112static driver_t ixpwdog_driver = {
113	"ixpwdog",
114	ixpwdog_methods,
115	sizeof(struct ixpwdog_softc),
116};
117static devclass_t ixpwdog_devclass;
118DRIVER_MODULE(ixpwdog, ixp, ixpwdog_driver, ixpwdog_devclass, 0, 0);
119