freebsd-dev/sys/arm/allwinner/aw_reset.c

165 lines
4.2 KiB
C

/*-
* Copyright (c) 2016 Jared McNeill <jmcneill@invisible.ca>
* All rights reserved.
*
* 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 AUTHOR ``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 AUTHOR 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.
*
* $FreeBSD$
*/
/*
* Allwinner module software reset registers
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/rman.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <machine/bus.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <dev/extres/hwreset/hwreset.h>
#include "hwreset_if.h"
#define RESET_OFFSET(index) ((index / 32) * 4)
#define RESET_SHIFT(index) (index % 32)
static struct ofw_compat_data compat_data[] = {
{ "allwinner,sun6i-a31-ahb1-reset", 1 },
{ "allwinner,sun6i-a31-clock-reset", 1 },
{ NULL, 0 }
};
struct aw_reset_softc {
struct resource *res;
struct mtx mtx;
};
static struct resource_spec aw_reset_spec[] = {
{ SYS_RES_MEMORY, 0, RF_ACTIVE },
{ -1, 0 }
};
#define RESET_READ(sc, reg) bus_read_4((sc)->res, (reg))
#define RESET_WRITE(sc, reg, val) bus_write_4((sc)->res, (reg), (val))
static int
aw_reset_assert(device_t dev, intptr_t id, bool reset)
{
struct aw_reset_softc *sc;
uint32_t reg_value;
sc = device_get_softc(dev);
mtx_lock(&sc->mtx);
reg_value = RESET_READ(sc, RESET_OFFSET(id));
if (reset)
reg_value &= ~(1 << RESET_SHIFT(id));
else
reg_value |= (1 << RESET_SHIFT(id));
RESET_WRITE(sc, RESET_OFFSET(id), reg_value);
mtx_unlock(&sc->mtx);
return (0);
}
static int
aw_reset_is_asserted(device_t dev, intptr_t id, bool *reset)
{
struct aw_reset_softc *sc;
uint32_t reg_value;
sc = device_get_softc(dev);
mtx_lock(&sc->mtx);
reg_value = RESET_READ(sc, RESET_OFFSET(id));
mtx_unlock(&sc->mtx);
*reset = (reg_value & (1 << RESET_SHIFT(id))) != 0 ? false : true;
return (0);
}
static int
aw_reset_probe(device_t dev)
{
if (!ofw_bus_status_okay(dev))
return (ENXIO);
if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
return (ENXIO);
device_set_desc(dev, "Allwinner Module Resets");
return (BUS_PROBE_DEFAULT);
}
static int
aw_reset_attach(device_t dev)
{
struct aw_reset_softc *sc;
sc = device_get_softc(dev);
if (bus_alloc_resources(dev, aw_reset_spec, &sc->res) != 0) {
device_printf(dev, "cannot allocate resources for device\n");
return (ENXIO);
}
mtx_init(&sc->mtx, device_get_nameunit(dev), NULL, MTX_DEF);
hwreset_register_ofw_provider(dev);
return (0);
}
static device_method_t aw_reset_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, aw_reset_probe),
DEVMETHOD(device_attach, aw_reset_attach),
/* Reset interface */
DEVMETHOD(hwreset_assert, aw_reset_assert),
DEVMETHOD(hwreset_is_asserted, aw_reset_is_asserted),
DEVMETHOD_END
};
static driver_t aw_reset_driver = {
"aw_reset",
aw_reset_methods,
sizeof(struct aw_reset_softc),
};
static devclass_t aw_reset_devclass;
EARLY_DRIVER_MODULE(aw_reset, simplebus, aw_reset_driver, aw_reset_devclass,
0, 0, BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
MODULE_VERSION(aw_reset, 1);