geodewdg.c revision 1.3 1 /* $NetBSD: geodewdg.c,v 1.3 2006/08/31 19:24:37 dyoung Exp $ */
2
3 /*-
4 * Copyright (c) 2005 David Young. All rights reserved.
5 *
6 * This code was written by David Young.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by David Young.
19 * 4. The name of David Young may not be used to endorse or promote
20 * products derived from this software without specific prior
21 * written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY DAVID YOUNG ``AS IS'' AND ANY
24 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
25 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
26 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DAVID
27 * YOUNG BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
28 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
31 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
32 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
34 * OF SUCH DAMAGE.
35 */
36 /*-
37 * Copyright (c) 2002 The NetBSD Foundation, Inc.
38 * All rights reserved.
39 *
40 * This code is derived from software contributed to The NetBSD Foundation
41 * by Jason R. Thorpe.
42 *
43 * Redistribution and use in source and binary forms, with or without
44 * modification, are permitted provided that the following conditions
45 * are met:
46 * 1. Redistributions of source code must retain the above copyright
47 * notice, this list of conditions and the following disclaimer.
48 * 2. Redistributions in binary form must reproduce the above copyright
49 * notice, this list of conditions and the following disclaimer in the
50 * documentation and/or other materials provided with the distribution.
51 * 3. All advertising materials mentioning features or use of this software
52 * must display the following acknowledgement:
53 * This product includes software developed by the NetBSD
54 * Foundation, Inc. and its contributors.
55 * 4. Neither the name of The NetBSD Foundation nor the names of its
56 * contributors may be used to endorse or promote products derived
57 * from this software without specific prior written permission.
58 *
59 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
60 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
61 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
62 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
63 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
64 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
65 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
66 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
67 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
68 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
69 * POSSIBILITY OF SUCH DAMAGE.
70 */
71
72 /*
73 * Device driver for the watchdog timer built into the
74 * AMD Geode SC1100 processor.
75 */
76
77 #include <sys/cdefs.h>
78
79 __KERNEL_RCSID(0, "$NetBSD: geodewdg.c,v 1.3 2006/08/31 19:24:37 dyoung Exp $");
80
81 #include <sys/param.h>
82 #include <sys/systm.h>
83 #include <sys/device.h>
84 #include <sys/wdog.h>
85 #include <uvm/uvm_extern.h>
86 #include <machine/bus.h>
87 #include <dev/pci/pcivar.h>
88 #include <dev/pci/pcidevs.h>
89 #include <arch/i386/pci/geodevar.h>
90 #include <arch/i386/pci/geodereg.h>
91 #include <dev/sysmon/sysmonvar.h>
92
93 #ifdef GEODE_DEBUG
94 #define GEODE_DPRINTF(__x) printf __x
95 #else /* GEODE_DEBUG */
96 #define GEODE_DPRINTF(__x) /* nothing */
97 #endif
98
99 struct geode_wdog_softc {
100 struct device sc_dev;
101 struct geode_gcb_softc *sc_gcb_dev;
102
103 uint16_t sc_countdown;
104 uint8_t sc_prescale;
105 struct sysmon_wdog sc_smw;
106 };
107
108 static int attached = 0;
109
110 static void
111 geode_wdog_disable(struct geode_wdog_softc *sc)
112 {
113 uint16_t wdcnfg;
114
115 /* cancel any pending countdown */
116 sc->sc_countdown = 0;
117 bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDTO, 0);
118 /* power-down clock */
119 wdcnfg = bus_space_read_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh,
120 SC1100_GCB_WDCNFG);
121
122 GEODE_DPRINTF(("%s: wdcnfg %#04" PRIx16 " -> ", __func__, wdcnfg));
123
124 wdcnfg |= SC1100_WDCNFG_WD32KPD;
125 wdcnfg &= ~(SC1100_WDCNFG_WDTYPE2_MASK | SC1100_WDCNFG_WDTYPE1_MASK);
126 /* This no-op is for the reader's benefit. */
127 wdcnfg |= SC1100_WDCNFG_WDTYPE1_NOACTION |
128 SC1100_WDCNFG_WDTYPE2_NOACTION;
129 bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDCNFG, wdcnfg);
130
131 GEODE_DPRINTF(("%#04" PRIx16 "\n", wdcnfg));
132 }
133
134 static void
135 geode_wdog_enable(struct geode_wdog_softc *sc)
136 {
137 uint16_t wdcnfg;
138
139 /* power-up clock and set prescale */
140 wdcnfg = bus_space_read_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDCNFG);
141
142 GEODE_DPRINTF(("%s: wdcnfg %#04" PRIx16 " -> ", __func__, wdcnfg));
143
144 wdcnfg &= ~(SC1100_WDCNFG_WD32KPD | SC1100_WDCNFG_WDPRES_MASK |
145 SC1100_WDCNFG_WDTYPE1_MASK | SC1100_WDCNFG_WDTYPE2_MASK);
146 wdcnfg |= __SHIFTIN(sc->sc_prescale, SC1100_WDCNFG_WDPRES_MASK);
147 wdcnfg |= SC1100_WDCNFG_WDTYPE1_RESET | SC1100_WDCNFG_WDTYPE2_NOACTION;
148
149 bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDCNFG, wdcnfg);
150
151 GEODE_DPRINTF(("%#04" PRIx16 "\n", wdcnfg));
152 }
153
154 static void
155 geode_wdog_reset(struct geode_wdog_softc *sc)
156 {
157 /* set countdown */
158 bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDTO,
159 sc->sc_countdown);
160 }
161
162 static int
163 geode_wdog_tickle(struct sysmon_wdog *smw)
164 {
165 int s;
166 struct geode_wdog_softc *sc = smw->smw_cookie;
167
168 s = splhigh();
169 geode_wdog_reset(sc);
170 splx(s);
171 return 0;
172 }
173
174 static int
175 geode_wdog_setmode(struct sysmon_wdog *smw)
176 {
177 struct geode_wdog_softc *sc = smw->smw_cookie;
178 uint32_t ticks;
179 int prescale, s;
180
181 if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
182 s = splhigh();
183 geode_wdog_disable(sc);
184 splx(s);
185 return 0;
186 }
187 if (smw->smw_period == WDOG_PERIOD_DEFAULT)
188 smw->smw_period = 32;
189 else if (smw->smw_period > SC1100_WDIVL_MAX) /* too big? */
190 return EINVAL;
191
192 GEODE_DPRINTF(("%s: period %u\n", __func__, smw->smw_period));
193
194 ticks = smw->smw_period * SC1100_WDCLK_HZ;
195
196 GEODE_DPRINTF(("%s: ticks0 %" PRIu32 "\n", __func__, ticks));
197
198 for (prescale = 0; ticks > UINT16_MAX; prescale++)
199 ticks /= 2;
200
201 GEODE_DPRINTF(("%s: ticks %" PRIu32 "\n", __func__, ticks));
202 GEODE_DPRINTF(("%s: prescale %d\n", __func__, prescale));
203
204 KASSERT(prescale <= SC1100_WDCNFG_WDPRES_MAX);
205 KASSERT(ticks <= UINT16_MAX);
206
207 s = splhigh();
208
209 sc->sc_prescale = (uint8_t)prescale;
210 sc->sc_countdown = (uint16_t)ticks;
211
212 geode_wdog_enable(sc);
213
214 geode_wdog_reset(sc);
215
216 splx(s);
217 return 0;
218 }
219
220 static int
221 geode_wdog_match(struct device *parent, struct cfdata *match, void *aux)
222 {
223 return !attached;
224 }
225
226 static void
227 geode_wdog_attach(struct device *parent, struct device *self, void *aux)
228 {
229 struct geode_wdog_softc *sc = (void *) self;
230 uint8_t wdsts;
231
232 aprint_naive(": Watchdog Timer\n");
233 aprint_normal(": AMD Geode SC1100 Watchdog Timer\n");
234
235
236 /*
237 * Hook up the watchdog timer.
238 */
239 sc->sc_gcb_dev = (struct geode_gcb_softc *)parent;
240 sc->sc_smw.smw_name = sc->sc_dev.dv_xname;
241 sc->sc_smw.smw_cookie = sc;
242 sc->sc_smw.smw_setmode = geode_wdog_setmode;
243 sc->sc_smw.smw_tickle = geode_wdog_tickle;
244 sc->sc_smw.smw_period = 32;
245
246 /*
247 * Determine cause of the last reset, and issue a warning if it
248 * was due to watchdog expiry.
249 */
250 wdsts = bus_space_read_1(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDSTS);
251
252 GEODE_DPRINTF(("%s: status %#02" PRIx8 "\n", sc->sc_dev.dv_xname,
253 wdsts));
254
255 if (wdsts & SC1100_WDSTS_WDRST)
256 aprint_error(
257 "%s: WARNING: LAST RESET DUE TO WATCHDOG EXPIRATION!\n",
258 sc->sc_dev.dv_xname);
259
260 /* reset WDOVF by writing 1 to it */
261 bus_space_write_1(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDSTS,
262 wdsts & SC1100_WDSTS_WDOVF);
263
264 if (sysmon_wdog_register(&sc->sc_smw) != 0)
265 aprint_error("%s: unable to register watchdog with sysmon\n",
266 sc->sc_dev.dv_xname);
267
268 /* cancel any pending countdown */
269 geode_wdog_disable(sc);
270
271 attached = 1;
272 }
273
274 CFATTACH_DECL(geodewdog, sizeof(struct geode_wdog_softc),
275 geode_wdog_match, geode_wdog_attach, NULL, NULL);
276