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      1 /* $NetBSD: admwdog.c,v 1.4 2012/10/27 17:18:01 chs Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 2007 David Young.  All rights reserved.
      5  *
      6  * Redistribution and use in source and binary forms, with or
      7  * without modification, are permitted provided that the following
      8  * conditions are met:
      9  * 1. Redistributions of source code must retain the above copyright
     10  *    notice, this list of conditions and the following disclaimer.
     11  * 2. Redistributions in binary form must reproduce the above
     12  *    copyright notice, this list of conditions and the following
     13  *    disclaimer in the documentation and/or other materials provided
     14  *    with the distribution.
     15  *
     16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY
     17  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
     18  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
     19  * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR
     20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
     21  * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     22  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
     23  * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
     25  * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
     26  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
     27  * OF SUCH DAMAGE.
     28  */
     29 
     30 #include <sys/cdefs.h>
     31 
     32 __KERNEL_RCSID(0, "$NetBSD: admwdog.c,v 1.4 2012/10/27 17:18:01 chs Exp $");
     33 
     34 #include <sys/param.h>
     35 #include <sys/systm.h>
     36 #include <sys/device.h>
     37 #include <sys/wdog.h>
     38 #include <sys/kernel.h>	/* for hz */
     39 
     40 #include <sys/bus.h>
     41 
     42 #include <dev/sysmon/sysmonvar.h>
     43 
     44 #include <mips/adm5120/include/adm5120reg.h>
     45 #include <mips/adm5120/include/adm5120var.h>
     46 #include <mips/adm5120/include/adm5120_obiovar.h>
     47 #include <mips/adm5120/dev/if_admswvar.h>
     48 
     49 /* maximum watchdog period, seconds */
     50 #define	ADMWDOG_MAX_PERIOD	(__SHIFTOUT_MASK(ADM5120_WDOG_WTS_MASK) / 100)
     51 
     52 static int admwdog_setmode(struct sysmon_wdog *smw);
     53 static int admwdog_tickle(struct sysmon_wdog *smw);
     54 
     55 static inline uint32_t
     56 admwdog_read(struct admsw_softc *sc)
     57 {
     58 	return bus_space_read_4(sc->sc_st, sc->sc_ioh, ADM5120_WDOG0);
     59 }
     60 
     61 static inline void
     62 admwdog_write(struct admsw_softc *sc, uint32_t val)
     63 {
     64 	bus_space_write_4(sc->sc_st, sc->sc_ioh, ADM5120_WDOG0, val);
     65 }
     66 
     67 static void
     68 admwdog_reset(struct admsw_softc *sc)
     69 {
     70 	int s;
     71 	uint32_t wdog0;
     72 
     73 	wdog0 = __SHIFTIN(sc->sc_smw.smw_period * 100, ADM5120_WDOG_WTS_MASK) |
     74 	    __SHIFTIN(1, ADM5120_WDOG_WT_MASK);
     75 
     76 	s = splhigh();
     77 
     78 	admwdog_write(sc, wdog0);
     79 	(void)admwdog_read(sc);
     80 	admwdog_write(sc, ADM5120_WDOG0_WTTR | wdog0);
     81 
     82 	splx(s);
     83 }
     84 
     85 static int
     86 admwdog_setmode(struct sysmon_wdog *smw)
     87 {
     88 	struct admsw_softc *sc = smw->smw_cookie;
     89 
     90 	if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
     91 		admwdog_write(sc, 0);
     92 		return 0;
     93 	}
     94 
     95 	if (smw->smw_period == WDOG_PERIOD_DEFAULT)
     96 		smw->smw_period = 32;
     97 	else if (smw->smw_period > ADMWDOG_MAX_PERIOD)
     98 		return EINVAL;
     99 
    100 	admwdog_reset(sc);
    101 
    102 	return 0;
    103 }
    104 
    105 static int
    106 admwdog_tickle(struct sysmon_wdog *smw)
    107 {
    108 	struct admsw_softc *sc = smw->smw_cookie;
    109 
    110 	(void)admwdog_read(sc);
    111 	return 0;
    112 }
    113 
    114 void
    115 admwdog_attach(struct admsw_softc *sc)
    116 {
    117 	struct sysmon_wdog *smw = &sc->sc_smw;
    118 
    119 	/* deactivate watchdog */
    120 	admwdog_write(sc, 0);
    121 
    122 	smw->smw_name = device_xname(sc->sc_dev);
    123 	smw->smw_cookie = sc;
    124 	smw->smw_setmode = admwdog_setmode;
    125 	smw->smw_tickle = admwdog_tickle;
    126 	smw->smw_period = ADMWDOG_MAX_PERIOD;
    127 
    128 	sysmon_wdog_register(&sc->sc_smw);
    129 }
    130