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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