1 /* $NetBSD: geodewdg.c,v 1.12 2016/07/11 11:31:49 msaitoh 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 *
17 * THIS SOFTWARE IS PROVIDED BY DAVID YOUNG ``AS IS'' AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
19 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
20 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DAVID
21 * YOUNG BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
22 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
23 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
25 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
26 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
28 * OF SUCH DAMAGE.
29 */
30 /*-
31 * Copyright (c) 2002 The NetBSD Foundation, Inc.
32 * All rights reserved.
33 *
34 * This code is derived from software contributed to The NetBSD Foundation
35 * by Jason R. Thorpe.
36 *
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 * notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 * notice, this list of conditions and the following disclaimer in the
44 * documentation and/or other materials provided with the distribution.
45 *
46 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
47 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
48 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
49 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
50 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
51 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
52 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
53 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
54 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
55 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
56 * POSSIBILITY OF SUCH DAMAGE.
57 */
58
59 /*
60 * Device driver for the watchdog timer built into the
61 * AMD Geode SC1100 processor.
62 */
63
64 #include <sys/cdefs.h>
65
66 __KERNEL_RCSID(0, "$NetBSD: geodewdg.c,v 1.12 2016/07/11 11:31:49 msaitoh Exp $");
67
68 #include <sys/param.h>
69 #include <sys/systm.h>
70 #include <sys/device.h>
71 #include <sys/wdog.h>
72 #include <uvm/uvm_extern.h>
73 #include <sys/bus.h>
74 #include <dev/pci/pcivar.h>
75 #include <dev/pci/pcidevs.h>
76 #include <arch/i386/pci/geodevar.h>
77 #include <arch/i386/pci/geodereg.h>
78 #include <dev/sysmon/sysmonvar.h>
79
80 #ifdef GEODE_DEBUG
81 #define GEODE_DPRINTF(__x) printf __x
82 #else /* GEODE_DEBUG */
83 #define GEODE_DPRINTF(__x) /* nothing */
84 #endif
85
86 struct geode_wdog_softc {
87 struct geode_gcb_softc *sc_gcb_dev;
88
89 uint16_t sc_countdown;
90 uint8_t sc_prescale;
91 struct sysmon_wdog sc_smw;
92 };
93
94 static int attached = 0;
95
96 static void
geode_wdog_disable(struct geode_wdog_softc * sc)97 geode_wdog_disable(struct geode_wdog_softc *sc)
98 {
99 uint16_t wdcnfg;
100
101 /* cancel any pending countdown */
102 sc->sc_countdown = 0;
103 bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh,
104 SC1100_GCB_WDTO, 0);
105 /* power-down clock */
106 wdcnfg = bus_space_read_2(sc->sc_gcb_dev->sc_iot,
107 sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDCNFG);
108
109 GEODE_DPRINTF(("%s: wdcnfg %#04" PRIx16 " -> ", __func__, wdcnfg));
110
111 wdcnfg |= SC1100_WDCNFG_WD32KPD;
112 wdcnfg &= ~(SC1100_WDCNFG_WDTYPE2_MASK | SC1100_WDCNFG_WDTYPE1_MASK);
113 /* This no-op is for the reader's benefit. */
114 wdcnfg |= SC1100_WDCNFG_WDTYPE1_NOACTION |
115 SC1100_WDCNFG_WDTYPE2_NOACTION;
116 bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh,
117 SC1100_GCB_WDCNFG, wdcnfg);
118
119 GEODE_DPRINTF(("%#04" PRIx16 "\n", wdcnfg));
120 }
121
122 static void
geode_wdog_enable(struct geode_wdog_softc * sc)123 geode_wdog_enable(struct geode_wdog_softc *sc)
124 {
125 uint16_t wdcnfg;
126
127 /* power-up clock and set prescale */
128 wdcnfg = bus_space_read_2(sc->sc_gcb_dev->sc_iot,
129 sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDCNFG);
130
131 GEODE_DPRINTF(("%s: wdcnfg %#04" PRIx16 " -> ", __func__, wdcnfg));
132
133 wdcnfg &= ~(SC1100_WDCNFG_WD32KPD | SC1100_WDCNFG_WDPRES_MASK |
134 SC1100_WDCNFG_WDTYPE1_MASK | SC1100_WDCNFG_WDTYPE2_MASK);
135 wdcnfg |= __SHIFTIN(sc->sc_prescale, SC1100_WDCNFG_WDPRES_MASK);
136 wdcnfg |= SC1100_WDCNFG_WDTYPE1_RESET | SC1100_WDCNFG_WDTYPE2_NOACTION;
137
138 bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh,
139 SC1100_GCB_WDCNFG, wdcnfg);
140
141 GEODE_DPRINTF(("%#04" PRIx16 "\n", wdcnfg));
142 }
143
144 static void
geode_wdog_reset(struct geode_wdog_softc * sc)145 geode_wdog_reset(struct geode_wdog_softc *sc)
146 {
147 /* set countdown */
148 bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh,
149 SC1100_GCB_WDTO, sc->sc_countdown);
150 }
151
152 static int
geode_wdog_tickle(struct sysmon_wdog * smw)153 geode_wdog_tickle(struct sysmon_wdog *smw)
154 {
155 int s;
156 struct geode_wdog_softc *sc = smw->smw_cookie;
157
158 s = splhigh();
159 geode_wdog_reset(sc);
160 splx(s);
161 return 0;
162 }
163
164 static int
geode_wdog_setmode(struct sysmon_wdog * smw)165 geode_wdog_setmode(struct sysmon_wdog *smw)
166 {
167 struct geode_wdog_softc *sc = smw->smw_cookie;
168 uint32_t ticks;
169 int prescale, s;
170
171 if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
172 s = splhigh();
173 geode_wdog_disable(sc);
174 splx(s);
175 return 0;
176 }
177 if (smw->smw_period == WDOG_PERIOD_DEFAULT)
178 smw->smw_period = 32;
179 else if (smw->smw_period > SC1100_WDIVL_MAX) /* too big? */
180 return EINVAL;
181
182 GEODE_DPRINTF(("%s: period %u\n", __func__, smw->smw_period));
183
184 ticks = smw->smw_period * SC1100_WDCLK_HZ;
185
186 GEODE_DPRINTF(("%s: ticks0 %" PRIu32 "\n", __func__, ticks));
187
188 for (prescale = 0; ticks > UINT16_MAX; prescale++)
189 ticks /= 2;
190
191 GEODE_DPRINTF(("%s: ticks %" PRIu32 "\n", __func__, ticks));
192 GEODE_DPRINTF(("%s: prescale %d\n", __func__, prescale));
193
194 KASSERT(prescale <= SC1100_WDCNFG_WDPRES_MAX);
195 KASSERT(ticks <= UINT16_MAX);
196
197 s = splhigh();
198
199 sc->sc_prescale = (uint8_t)prescale;
200 sc->sc_countdown = (uint16_t)ticks;
201
202 geode_wdog_enable(sc);
203
204 geode_wdog_reset(sc);
205
206 splx(s);
207 return 0;
208 }
209
210 static int
geode_wdog_match(device_t parent,cfdata_t match,void * aux)211 geode_wdog_match(device_t parent, cfdata_t match, void *aux)
212 {
213 return !attached;
214 }
215
216 static void
geode_wdog_attach(device_t parent,device_t self,void * aux)217 geode_wdog_attach(device_t parent, device_t self, void *aux)
218 {
219 struct geode_wdog_softc *sc = device_private(self);
220 uint8_t wdsts;
221
222 aprint_naive(": Watchdog Timer\n");
223 aprint_normal(": AMD Geode SC1100 Watchdog Timer\n");
224
225
226 /*
227 * Hook up the watchdog timer.
228 */
229 sc->sc_gcb_dev = device_private(parent);
230 sc->sc_smw.smw_name = device_xname(self);
231 sc->sc_smw.smw_cookie = sc;
232 sc->sc_smw.smw_setmode = geode_wdog_setmode;
233 sc->sc_smw.smw_tickle = geode_wdog_tickle;
234 sc->sc_smw.smw_period = 32;
235
236 /*
237 * Determine cause of the last reset, and issue a warning if it
238 * was due to watchdog expiry.
239 */
240 wdsts = bus_space_read_1(sc->sc_gcb_dev->sc_iot,
241 sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDSTS);
242
243 GEODE_DPRINTF(("%s: status %#02" PRIx8 "\n", device_xname(self),
244 wdsts));
245
246 if (wdsts & SC1100_WDSTS_WDRST)
247 aprint_error(
248 "%s: WARNING: LAST RESET DUE TO WATCHDOG EXPIRATION!\n",
249 device_xname(self));
250
251 /* reset WDOVF by writing 1 to it */
252 bus_space_write_1(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh,
253 SC1100_GCB_WDSTS, wdsts & SC1100_WDSTS_WDOVF);
254
255 if (sysmon_wdog_register(&sc->sc_smw) != 0)
256 aprint_error("%s: unable to register watchdog with sysmon\n",
257 device_xname(self));
258
259 /* cancel any pending countdown */
260 geode_wdog_disable(sc);
261
262 attached = 1;
263 }
264
265 static int
geode_wdog_detach(device_t self,int flags)266 geode_wdog_detach(device_t self, int flags)
267 {
268 int rc;
269 struct geode_wdog_softc *sc = device_private(self);
270
271 if ((rc = sysmon_wdog_unregister(&sc->sc_smw)) != 0) {
272 if (rc == ERESTART)
273 rc = EINTR;
274 return rc;
275 }
276
277 /* cancel any pending countdown */
278 geode_wdog_disable(sc);
279
280 attached = 0;
281
282 return 0;
283 }
284
285 CFATTACH_DECL_NEW(geodewdog, sizeof(struct geode_wdog_softc),
286 geode_wdog_match, geode_wdog_attach, geode_wdog_detach, NULL);
287