xref: /netbsd-src/sys/arch/arm/xscale/ixp425_wdog.c (revision a5847cc334d9a7029f6352b847e9e8d71a0f9e0c)
1 /*	$NetBSD: ixp425_wdog.c,v 1.3 2011/07/01 20:32:51 dyoung Exp $	*/
2 
3 /*-
4  * Copyright (c) 2006 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Steve C. Woodford.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include "opt_ddb.h"
33 
34 #include <sys/cdefs.h>
35 __KERNEL_RCSID(0, "$NetBSD: ixp425_wdog.c,v 1.3 2011/07/01 20:32:51 dyoung Exp $");
36 
37 #include <sys/systm.h>
38 #include <sys/param.h>
39 #include <sys/kernel.h>
40 #include <sys/device.h>
41 #include <sys/wdog.h>
42 
43 #include <dev/clock_subr.h>
44 #include <dev/sysmon/sysmonvar.h>
45 
46 #include <machine/intr.h>
47 #include <sys/bus.h>
48 
49 #include <arm/xscale/ixp425reg.h>
50 #include <arm/xscale/ixp425var.h>
51 #include <arm/xscale/ixp425_sipvar.h>
52 
53 #ifdef DDB
54 #include <machine/db_machdep.h>
55 #include <ddb/db_extern.h>
56 #endif
57 
58 struct ixpdog_softc {
59 	struct device sc_dev;
60 	struct sysmon_wdog sc_smw;
61 	bus_space_tag_t sc_bust;
62 	bus_space_handle_t sc_bush;
63 	uint32_t sc_preset;
64 	int sc_armed;
65 };
66 
67 #define	IXPDOG_DEFAULT_PERIOD	8
68 #ifndef	IXP425_CLOCK_FREQ
69 #define	IXPDOG_COUNTS_PER_SEC	66666600
70 #else
71 #define	IXPDOG_COUNTS_PER_SEC	IXP425_CLOCK_FREQ
72 #endif
73 
74 static int ixpdog_match(struct device *, struct cfdata *, void *);
75 static void ixpdog_attach(struct device *, struct device *, void *);
76 
77 CFATTACH_DECL(ixpdog, sizeof(struct ixpdog_softc),
78     ixpdog_match, ixpdog_attach, NULL, NULL);
79 
80 static void ixpdog_control(struct ixpdog_softc *, int);
81 static int ixpdog_tickle(struct sysmon_wdog *);
82 static int ixpdog_setmode(struct sysmon_wdog *);
83 
84 #ifdef DDB
85 static struct ixpdog_softc *ixpdog_softc;
86 static void ixpdog_ddb_trap(int);
87 #endif
88 
89 
90 static int
91 ixpdog_match(struct device *parent, struct cfdata *match, void *arg)
92 {
93 	struct ixpsip_attach_args *sa = arg;
94 
95 	return (sa->sa_addr == IXP425_OST_WDOG_HWBASE);
96 }
97 
98 static void
99 ixpdog_attach(struct device *parent, struct device *self, void *arg)
100 {
101 	struct ixpdog_softc *sc = (struct ixpdog_softc *)self;
102 	struct ixpsip_attach_args *sa = arg;
103 
104 	aprint_naive("\n");
105 	aprint_normal(": Watchdog Timer\n");
106 
107 	sc->sc_bust = sa->sa_iot;
108 
109 	if (bus_space_map(sc->sc_bust, sa->sa_addr, IXP425_OST_WDOG_SIZE, 0,
110 	    &sc->sc_bush)) {
111 		aprint_error("%s: Failed to map watchdog registers\n",
112 		    sc->sc_dev.dv_xname);
113 		return;
114 	}
115 
116 	sc->sc_preset = IXPDOG_COUNTS_PER_SEC * hz * IXPDOG_DEFAULT_PERIOD;
117 	sc->sc_armed = 0;
118 	ixpdog_control(sc, 0);
119 
120 #ifdef DDB
121 	ixpdog_softc = sc;
122 	db_trap_callback = ixpdog_ddb_trap;
123 #endif
124 
125 	sc->sc_smw.smw_name = sc->sc_dev.dv_xname;
126 	sc->sc_smw.smw_cookie = sc;
127 	sc->sc_smw.smw_setmode = ixpdog_setmode;
128 	sc->sc_smw.smw_tickle = ixpdog_tickle;
129 	sc->sc_smw.smw_period = IXPDOG_DEFAULT_PERIOD;
130 
131 	if (sysmon_wdog_register(&sc->sc_smw) != 0)
132 		aprint_error("%s: unable to register watchdog with sysmon\n",
133 		    sc->sc_dev.dv_xname);
134 }
135 
136 static void
137 ixpdog_control(struct ixpdog_softc *sc, int enable)
138 {
139 	uint32_t reg;
140 	int s;
141 
142 	s = disable_interrupts(I32_bit);
143 	bus_space_write_2(sc->sc_bust, sc->sc_bush, IXP425_OST_WDOG_KEY,
144 	    OST_WDOG_KEY_MAJICK);
145 	reg = bus_space_read_4(sc->sc_bust, sc->sc_bush, IXP425_OST_WDOG_ENAB);
146 
147 	if (!enable)
148 		reg &= ~(OST_WDOG_ENAB_CNT_ENA | OST_WDOG_ENAB_RST_ENA);
149 	else {
150 		bus_space_write_4(sc->sc_bust, sc->sc_bush, IXP425_OST_WDOG,
151 		    sc->sc_preset);
152 		reg |= OST_WDOG_ENAB_CNT_ENA | OST_WDOG_ENAB_RST_ENA;
153 	}
154 
155 	bus_space_write_4(sc->sc_bust, sc->sc_bush, IXP425_OST_WDOG_ENAB, reg);
156 	bus_space_write_2(sc->sc_bust, sc->sc_bush, IXP425_OST_WDOG_KEY,
157 	    ~OST_WDOG_KEY_MAJICK);
158 	restore_interrupts(s);
159 }
160 
161 static int
162 ixpdog_tickle(struct sysmon_wdog *smw)
163 {
164 	struct ixpdog_softc *sc = smw->smw_cookie;
165 	int s;
166 
167 	s = disable_interrupts(I32_bit);
168 	bus_space_write_2(sc->sc_bust, sc->sc_bush, IXP425_OST_WDOG_KEY,
169 	    OST_WDOG_KEY_MAJICK);
170 	bus_space_write_4(sc->sc_bust, sc->sc_bush, IXP425_OST_WDOG,
171 	    sc->sc_preset);
172 	bus_space_write_2(sc->sc_bust, sc->sc_bush, IXP425_OST_WDOG_KEY,
173 	    ~OST_WDOG_KEY_MAJICK);
174 	restore_interrupts(s);
175 
176 	return (0);
177 }
178 
179 static int
180 ixpdog_setmode(struct sysmon_wdog *smw)
181 {
182 	struct ixpdog_softc *sc = smw->smw_cookie;
183 
184 	if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED)
185 		sc->sc_armed = 0;
186 	else {
187 		if (smw->smw_period == WDOG_PERIOD_DEFAULT)
188 			smw->smw_period = IXPDOG_DEFAULT_PERIOD;
189 		sc->sc_preset = IXPDOG_COUNTS_PER_SEC * hz * smw->smw_period;
190 		if (sc->sc_preset < (IXPDOG_COUNTS_PER_SEC * hz) ||
191 		    sc->sc_preset < smw->smw_period)
192 			return (EOPNOTSUPP);
193 
194 		sc->sc_armed = 1;
195 	}
196 
197 	ixpdog_control(sc, sc->sc_armed);
198 
199 	return (0);
200 }
201 
202 #ifdef DDB
203 static void
204 ixpdog_ddb_trap(int enter)
205 {
206 	struct ixpdog_softc *sc;
207 
208 	if ((sc = ixpdog_softc) == NULL)
209 		return;
210 
211 	sc->sc_armed += enter ? (-1) : 1;
212 
213 	if ((enter && sc->sc_armed == 0) || (!enter && sc->sc_armed == 1))
214 		ixpdog_control(sc, sc->sc_armed);
215 }
216 #endif
217