freebsd-dev/sys/dev/extres/syscon/syscon_generic.c

208 lines
5.7 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2015 Michal Meloun
* 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 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 AUTHOR 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.
*/
/*
* This is a generic syscon driver, whose purpose is to provide access to
* various unrelated bits packed in a single register space. It is usually used
* as a fallback to more specific driver, but works well enough for simple
* access.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/rman.h>
#include <machine/bus.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include "syscon_if.h"
#include "syscon.h"
#include "syscon_generic.h"
MALLOC_DECLARE(M_SYSCON);
static uint32_t syscon_generic_read_4(struct syscon *syscon, bus_size_t offset);
static int syscon_generic_write_4(struct syscon *syscon, bus_size_t offset,
uint32_t val);
static int syscon_generic_modify_4(struct syscon *syscon, bus_size_t offset,
uint32_t clear_bits, uint32_t set_bits);
/*
* Generic syscon driver (FDT)
*/
static struct ofw_compat_data compat_data[] = {
{"syscon", 1},
{NULL, 0}
};
#define SYSCON_LOCK(_sc) mtx_lock_spin(&(_sc)->mtx)
#define SYSCON_UNLOCK(_sc) mtx_unlock_spin(&(_sc)->mtx)
#define SYSCON_LOCK_INIT(_sc) mtx_init(&(_sc)->mtx, \
device_get_nameunit((_sc)->dev), "syscon", MTX_SPIN)
#define SYSCON_LOCK_DESTROY(_sc) mtx_destroy(&(_sc)->mtx);
#define SYSCON_ASSERT_LOCKED(_sc) mtx_assert(&(_sc)->mtx, MA_OWNED);
#define SYSCON_ASSERT_UNLOCKED(_sc) mtx_assert(&(_sc)->mtx, MA_NOTOWNED);
static syscon_method_t syscon_generic_methods[] = {
SYSCONMETHOD(syscon_read_4, syscon_generic_read_4),
SYSCONMETHOD(syscon_write_4, syscon_generic_write_4),
SYSCONMETHOD(syscon_modify_4, syscon_generic_modify_4),
SYSCONMETHOD_END
};
DEFINE_CLASS_1(syscon_generic, syscon_generic_class, syscon_generic_methods,
0, syscon_class);
static uint32_t
syscon_generic_read_4(struct syscon *syscon, bus_size_t offset)
{
struct syscon_generic_softc *sc;
uint32_t val;
sc = device_get_softc(syscon->pdev);
SYSCON_LOCK(sc);
val = bus_read_4(sc->mem_res, offset);
SYSCON_UNLOCK(sc);
return (val);
}
static int
syscon_generic_write_4(struct syscon *syscon, bus_size_t offset, uint32_t val)
{
struct syscon_generic_softc *sc;
sc = device_get_softc(syscon->pdev);
SYSCON_LOCK(sc);
bus_write_4(sc->mem_res, offset, val);
SYSCON_UNLOCK(sc);
return (0);
}
static int
syscon_generic_modify_4(struct syscon *syscon, bus_size_t offset,
uint32_t clear_bits, uint32_t set_bits)
{
struct syscon_generic_softc *sc;
uint32_t val;
sc = device_get_softc(syscon->pdev);
SYSCON_LOCK(sc);
val = bus_read_4(sc->mem_res, offset);
val &= ~clear_bits;
val |= set_bits;
bus_write_4(sc->mem_res, offset, val);
SYSCON_UNLOCK(sc);
return (0);
}
static int
syscon_generic_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, "syscon");
return (BUS_PROBE_GENERIC);
}
static int
syscon_generic_attach(device_t dev)
{
struct syscon_generic_softc *sc;
int rid;
sc = device_get_softc(dev);
sc->dev = dev;
rid = 0;
sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
RF_ACTIVE);
if (sc->mem_res == NULL) {
device_printf(dev, "Cannot allocate memory resource\n");
return (ENXIO);
}
SYSCON_LOCK_INIT(sc);
sc->syscon = syscon_create_ofw_node(dev, &syscon_generic_class,
ofw_bus_get_node(dev));
if (sc->syscon == NULL) {
device_printf(dev, "Failed to create/register syscon\n");
return (ENXIO);
}
return (0);
}
static int
syscon_generic_detach(device_t dev)
{
struct syscon_generic_softc *sc;
sc = device_get_softc(dev);
if (sc->syscon != NULL) {
syscon_unregister(sc->syscon);
free(sc->syscon, M_SYSCON);
}
SYSCON_LOCK_DESTROY(sc);
if (sc->mem_res != NULL)
bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->mem_res);
return (0);
}
static device_method_t syscon_generic_dmethods[] = {
/* Device interface */
DEVMETHOD(device_probe, syscon_generic_probe),
DEVMETHOD(device_attach, syscon_generic_attach),
DEVMETHOD(device_detach, syscon_generic_detach),
DEVMETHOD_END
};
DEFINE_CLASS_0(syscon_generic, syscon_generic_driver, syscon_generic_dmethods,
sizeof(struct syscon_generic_softc));
static devclass_t syscon_generic_devclass;
EARLY_DRIVER_MODULE(syscon_generic, simplebus, syscon_generic_driver,
syscon_generic_devclass, 0, 0, BUS_PASS_DEFAULT);
MODULE_VERSION(syscon_generic, 1);