sys/arch/i386/pci/geodewdg.c

   1 /*      $NetBSD: geodewdg.c,v 1.9 2008/05/05 11:49:40 xtraeme 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 1.9 2008/05/05 11:49:40 xtraeme 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 <machine/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
  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
 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
 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
 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
 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
 211 geode_wdog_match(device_t parent, cfdata_t match, void *aux)
 212 {
 213         return !attached;
 214 }
 215
 216 static void
 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, sc->sc_gcb_dev->sc_ioh,
 241             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
 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);