1/*	$NetBSD: i80321_wdog.c,v 1.9 2011/07/01 20:32:51 dyoung Exp $	*/
2
3/*
4 * Copyright (c) 2002 Wasabi Systems, Inc.
5 * All rights reserved.
6 *
7 * Written by Jason R. Thorpe for Wasabi Systems, Inc.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 *    must display the following acknowledgement:
19 *	This product includes software developed for the NetBSD Project by
20 *	Wasabi Systems, Inc.
21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22 *    or promote products derived from this software without specific prior
23 *    written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
36 */
37
38/*
39 * Watchdog timer support for the Intel i80321 I/O processor.
40 */
41
42#include <sys/cdefs.h>
43__KERNEL_RCSID(0, "$NetBSD: i80321_wdog.c,v 1.9 2011/07/01 20:32:51 dyoung Exp $");
44
45#include <sys/param.h>
46#include <sys/systm.h>
47#include <sys/device.h>
48#include <sys/wdog.h>
49
50#include <sys/bus.h>
51#include <arm/cpufunc.h>
52
53#include <arm/xscale/i80321reg.h>
54#include <arm/xscale/i80321var.h>
55
56#include <dev/sysmon/sysmonvar.h>
57
58struct iopwdog_softc {
59	device_t sc_dev;
60	struct sysmon_wdog sc_smw;
61	int sc_wdog_armed;
62	int sc_wdog_period;
63};
64
65static inline void
66wdtcr_write(uint32_t val)
67{
68
69	__asm volatile("mcr p6, 0, %0, c7, c1, 0"
70		:
71		: "r" (val));
72}
73
74static int
75iopwdog_tickle(struct sysmon_wdog *smw)
76{
77
78	wdtcr_write(WDTCR_ENABLE1);
79	wdtcr_write(WDTCR_ENABLE2);
80	return (0);
81}
82
83static int
84iopwdog_setmode(struct sysmon_wdog *smw)
85{
86	struct iopwdog_softc *sc = smw->smw_cookie;
87
88	if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
89		/* The i80321 watchdog can't be disarmed once armed. */
90		if (sc->sc_wdog_armed)
91			return (EOPNOTSUPP);
92	} else {
93		if (smw->smw_period == WDOG_PERIOD_DEFAULT)
94			smw->smw_period = sc->sc_wdog_period;
95		else if (smw->smw_period != sc->sc_wdog_period) {
96			/* Can't change the i80321 watchdog period. */
97			return (EOPNOTSUPP);
98		}
99		sc->sc_wdog_armed = 1;
100		/* Watchdog is armed by tickling it. */
101		iopwdog_tickle(smw);
102	}
103	return (0);
104}
105
106static int
107iopwdog_match(device_t parent, cfdata_t cf, void *aux)
108{
109	struct iopxs_attach_args *ia = aux;
110
111	if (strcmp(cf->cf_name, ia->ia_name) == 0)
112		return (1);
113
114	return (0);
115}
116
117static void
118iopwdog_attach(device_t parent, device_t self, void *aux)
119{
120	struct iopwdog_softc *sc = device_private(self);
121	const char *xname = device_xname(self);
122
123	sc->sc_dev = self;
124	/*
125	 * XXX Should compute the period based on processor speed.
126	 * For a 600MHz XScale core, the wdog must be tickled approx.
127	 * every 7 seconds.
128	 */
129	sc->sc_wdog_period = 7;
130
131	aprint_naive(": Watchdog timer\n");
132	aprint_normal(": %d second period\n", sc->sc_wdog_period);
133
134	sc->sc_smw.smw_name = xname;
135	sc->sc_smw.smw_cookie = sc;
136	sc->sc_smw.smw_setmode = iopwdog_setmode;
137	sc->sc_smw.smw_tickle = iopwdog_tickle;
138	sc->sc_smw.smw_period = sc->sc_wdog_period;
139
140	if (sysmon_wdog_register(&sc->sc_smw) != 0)
141		aprint_error_dev(sc->sc_dev,
142		    "unable to register with sysmon\n");
143}
144
145CFATTACH_DECL_NEW(iopwdog, sizeof(struct iopwdog_softc),
146    iopwdog_match, iopwdog_attach, NULL, NULL);
147