1 /* $NetBSD: i80321_wdog.c,v 1.10 2012/02/12 16:31:01 matt 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 1.10 2012/02/12 16:31:01 matt 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
58 struct 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
65 static inline void
wdtcr_write(uint32_t val)66 wdtcr_write(uint32_t val)
67 {
68
69 __asm volatile("mcr p6, 0, %0, c7, c1, 0"
70 :
71 : "r" (val));
72 }
73
74 static int
iopwdog_tickle(struct sysmon_wdog * smw)75 iopwdog_tickle(struct sysmon_wdog *smw)
76 {
77
78 wdtcr_write(WDTCR_ENABLE1);
79 wdtcr_write(WDTCR_ENABLE2);
80 return (0);
81 }
82
83 static int
iopwdog_setmode(struct sysmon_wdog * smw)84 iopwdog_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
106 static int
iopwdog_match(device_t parent,cfdata_t cf,void * aux)107 iopwdog_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
117 static void
iopwdog_attach(device_t parent,device_t self,void * aux)118 iopwdog_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
145 CFATTACH_DECL_NEW(iopwdog, sizeof(struct iopwdog_softc),
146 iopwdog_match, iopwdog_attach, NULL, NULL);
147