/* $NetBSD: geodewdg.c,v 1.12 2016/07/11 11:31:49 msaitoh Exp $ */
/*-
* Copyright (c) 2005 David Young. All rights reserved.
*
* This code was written by David Young.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY DAVID YOUNG ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DAVID
* YOUNG BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*/
/*-
* Copyright (c) 2002 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Device driver for the watchdog timer built into the
* AMD Geode SC1100 processor.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: geodewdg.c,v 1.12 2016/07/11 11:31:49 msaitoh Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/wdog.h>
#include <uvm/uvm_extern.h>
#include <sys/bus.h>
#include <dev/pci/pcivar.h>
#include <dev/pci/pcidevs.h>
#include <arch/i386/pci/geodevar.h>
#include <arch/i386/pci/geodereg.h>
#include <dev/sysmon/sysmonvar.h>
#ifdef GEODE_DEBUG
#define GEODE_DPRINTF(__x) printf __x
#else /* GEODE_DEBUG */
#define GEODE_DPRINTF(__x) /* nothing */
#endif
struct geode_wdog_softc {
struct geode_gcb_softc *sc_gcb_dev;
uint16_t sc_countdown;
uint8_t sc_prescale;
struct sysmon_wdog sc_smw;
};
static int attached = 0;
static void
geode_wdog_disable(struct geode_wdog_softc *sc)
{
uint16_t wdcnfg;
/* cancel any pending countdown */
sc->sc_countdown = 0;
bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh,
SC1100_GCB_WDTO, 0);
/* power-down clock */
wdcnfg = bus_space_read_2(sc->sc_gcb_dev->sc_iot,
sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDCNFG);
GEODE_DPRINTF(("%s: wdcnfg %#04" PRIx16 " -> ", __func__, wdcnfg));
wdcnfg |= SC1100_WDCNFG_WD32KPD;
wdcnfg &= ~(SC1100_WDCNFG_WDTYPE2_MASK | SC1100_WDCNFG_WDTYPE1_MASK);
/* This no-op is for the reader's benefit. */
wdcnfg |= SC1100_WDCNFG_WDTYPE1_NOACTION |
SC1100_WDCNFG_WDTYPE2_NOACTION;
bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh,
SC1100_GCB_WDCNFG, wdcnfg);
GEODE_DPRINTF(("%#04" PRIx16 "\n", wdcnfg));
}
static void
geode_wdog_enable(struct geode_wdog_softc *sc)
{
uint16_t wdcnfg;
/* power-up clock and set prescale */
wdcnfg = bus_space_read_2(sc->sc_gcb_dev->sc_iot,
sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDCNFG);
GEODE_DPRINTF(("%s: wdcnfg %#04" PRIx16 " -> ", __func__, wdcnfg));
wdcnfg &= ~(SC1100_WDCNFG_WD32KPD | SC1100_WDCNFG_WDPRES_MASK |
SC1100_WDCNFG_WDTYPE1_MASK | SC1100_WDCNFG_WDTYPE2_MASK);
wdcnfg |= __SHIFTIN(sc->sc_prescale, SC1100_WDCNFG_WDPRES_MASK);
wdcnfg |= SC1100_WDCNFG_WDTYPE1_RESET | SC1100_WDCNFG_WDTYPE2_NOACTION;
bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh,
SC1100_GCB_WDCNFG, wdcnfg);
GEODE_DPRINTF(("%#04" PRIx16 "\n", wdcnfg));
}
static void
geode_wdog_reset(struct geode_wdog_softc *sc)
{
/* set countdown */
bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh,
SC1100_GCB_WDTO, sc->sc_countdown);
}
static int
geode_wdog_tickle(struct sysmon_wdog *smw)
{
int s;
struct geode_wdog_softc *sc = smw->smw_cookie;
s = splhigh();
geode_wdog_reset(sc);
splx(s);
return 0;
}
static int
geode_wdog_setmode(struct sysmon_wdog *smw)
{
struct geode_wdog_softc *sc = smw->smw_cookie;
uint32_t ticks;
int prescale, s;
if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
s = splhigh();
geode_wdog_disable(sc);
splx(s);
return 0;
}
if (smw->smw_period == WDOG_PERIOD_DEFAULT)
smw->smw_period = 32;
else if (smw->smw_period > SC1100_WDIVL_MAX) /* too big? */
return EINVAL;
GEODE_DPRINTF(("%s: period %u\n", __func__, smw->smw_period));
ticks = smw->smw_period * SC1100_WDCLK_HZ;
GEODE_DPRINTF(("%s: ticks0 %" PRIu32 "\n", __func__, ticks));
for (prescale = 0; ticks > UINT16_MAX; prescale++)
ticks /= 2;
GEODE_DPRINTF(("%s: ticks %" PRIu32 "\n", __func__, ticks));
GEODE_DPRINTF(("%s: prescale %d\n", __func__, prescale));
KASSERT(prescale <= SC1100_WDCNFG_WDPRES_MAX);
KASSERT(ticks <= UINT16_MAX);
s = splhigh();
sc->sc_prescale = (uint8_t)prescale;
sc->sc_countdown = (uint16_t)ticks;
geode_wdog_enable(sc);
geode_wdog_reset(sc);
splx(s);
return 0;
}
static int
geode_wdog_match(device_t parent, cfdata_t match, void *aux)
{
return !attached;
}
static void
geode_wdog_attach(device_t parent, device_t self, void *aux)
{
struct geode_wdog_softc *sc = device_private(self);
uint8_t wdsts;
aprint_naive(": Watchdog Timer\n");
aprint_normal(": AMD Geode SC1100 Watchdog Timer\n");
/*
* Hook up the watchdog timer.
*/
sc->sc_gcb_dev = device_private(parent);
sc->sc_smw.smw_name = device_xname(self);
sc->sc_smw.smw_cookie = sc;
sc->sc_smw.smw_setmode = geode_wdog_setmode;
sc->sc_smw.smw_tickle = geode_wdog_tickle;
sc->sc_smw.smw_period = 32;
/*
* Determine cause of the last reset, and issue a warning if it
* was due to watchdog expiry.
*/
wdsts = bus_space_read_1(sc->sc_gcb_dev->sc_iot,
sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDSTS);
GEODE_DPRINTF(("%s: status %#02" PRIx8 "\n", device_xname(self),
wdsts));
if (wdsts & SC1100_WDSTS_WDRST)
aprint_error(
"%s: WARNING: LAST RESET DUE TO WATCHDOG EXPIRATION!\n",
device_xname(self));
/* reset WDOVF by writing 1 to it */
bus_space_write_1(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh,
SC1100_GCB_WDSTS, wdsts & SC1100_WDSTS_WDOVF);
if (sysmon_wdog_register(&sc->sc_smw) != 0)
aprint_error("%s: unable to register watchdog with sysmon\n",
device_xname(self));
/* cancel any pending countdown */
geode_wdog_disable(sc);
attached = 1;
}
static int
geode_wdog_detach(device_t self, int flags)
{
int rc;
struct geode_wdog_softc *sc = device_private(self);
if ((rc = sysmon_wdog_unregister(&sc->sc_smw)) != 0) {
if (rc == ERESTART)
rc = EINTR;
return rc;
}
/* cancel any pending countdown */
geode_wdog_disable(sc);
attached = 0;
return 0;
}
CFATTACH_DECL_NEW(geodewdog, sizeof(struct geode_wdog_softc),
geode_wdog_match, geode_wdog_attach, geode_wdog_detach, NULL);