2015-03-31 11:50:46 +00:00
|
|
|
/*-
|
|
|
|
* Copyright 2014 John Wehle <john@feith.com>
|
|
|
|
* 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.
|
|
|
|
*/
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Amlogic aml8726 random number generator driver.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include <sys/cdefs.h>
|
|
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
|
|
|
|
#include <sys/param.h>
|
|
|
|
#include <sys/systm.h>
|
|
|
|
#include <sys/conf.h>
|
|
|
|
#include <sys/bus.h>
|
|
|
|
#include <sys/kernel.h>
|
|
|
|
#include <sys/module.h>
|
|
|
|
#include <sys/lock.h>
|
|
|
|
#include <sys/mutex.h>
|
|
|
|
#include <sys/resource.h>
|
|
|
|
#include <sys/rman.h>
|
|
|
|
#include <sys/random.h>
|
|
|
|
|
|
|
|
#include <machine/bus.h>
|
|
|
|
|
|
|
|
#include <dev/fdt/fdt_common.h>
|
|
|
|
#include <dev/ofw/ofw_bus.h>
|
|
|
|
#include <dev/ofw/ofw_bus_subr.h>
|
|
|
|
|
|
|
|
|
|
|
|
struct aml8726_rng_softc {
|
|
|
|
device_t dev;
|
|
|
|
struct resource *res[1];
|
|
|
|
struct callout co;
|
|
|
|
int ticks;
|
|
|
|
};
|
|
|
|
|
|
|
|
static struct resource_spec aml8726_rng_spec[] = {
|
|
|
|
{ SYS_RES_MEMORY, 0, RF_ACTIVE },
|
|
|
|
{ -1, 0 }
|
|
|
|
};
|
|
|
|
|
|
|
|
#define AML_RNG_0_REG 0
|
|
|
|
#define AML_RNG_1_REG 4
|
|
|
|
|
|
|
|
#define CSR_READ_4(sc, reg) bus_read_4((sc)->res[0], reg)
|
|
|
|
|
|
|
|
static void
|
|
|
|
aml8726_rng_harvest(void *arg)
|
|
|
|
{
|
|
|
|
struct aml8726_rng_softc *sc = arg;
|
|
|
|
uint32_t rn[2];
|
|
|
|
|
|
|
|
rn[0] = CSR_READ_4(sc, AML_RNG_0_REG);
|
|
|
|
rn[1] = CSR_READ_4(sc, AML_RNG_1_REG);
|
|
|
|
|
|
|
|
random_harvest(rn, sizeof(rn), sizeof(rn) * NBBY / 2,
|
|
|
|
RANDOM_PURE_AML8726);
|
|
|
|
|
|
|
|
callout_reset(&sc->co, sc->ticks, aml8726_rng_harvest, sc);
|
|
|
|
}
|
|
|
|
|
|
|
|
static int
|
|
|
|
aml8726_rng_probe(device_t dev)
|
|
|
|
{
|
|
|
|
|
|
|
|
if (!ofw_bus_status_okay(dev))
|
|
|
|
return (ENXIO);
|
|
|
|
|
|
|
|
if (!ofw_bus_is_compatible(dev, "amlogic,aml8726-rng"))
|
|
|
|
return (ENXIO);
|
|
|
|
|
|
|
|
device_set_desc(dev, "Amlogic aml8726 RNG");
|
|
|
|
|
|
|
|
return (BUS_PROBE_DEFAULT);
|
|
|
|
}
|
|
|
|
|
|
|
|
static int
|
|
|
|
aml8726_rng_attach(device_t dev)
|
|
|
|
{
|
|
|
|
struct aml8726_rng_softc *sc = device_get_softc(dev);
|
|
|
|
|
|
|
|
sc->dev = dev;
|
|
|
|
|
|
|
|
if (bus_alloc_resources(dev, aml8726_rng_spec, sc->res)) {
|
|
|
|
device_printf(dev, "can not allocate resources for device\n");
|
|
|
|
return (ENXIO);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Install a periodic collector for the RNG */
|
|
|
|
if (hz > 100)
|
|
|
|
sc->ticks = hz / 100;
|
|
|
|
else
|
|
|
|
sc->ticks = 1;
|
|
|
|
|
2015-05-22 17:05:21 +00:00
|
|
|
callout_init(&sc->co, 1);
|
2015-03-31 11:50:46 +00:00
|
|
|
callout_reset(&sc->co, sc->ticks, aml8726_rng_harvest, sc);
|
|
|
|
|
|
|
|
return (0);
|
|
|
|
}
|
|
|
|
|
|
|
|
static int
|
|
|
|
aml8726_rng_detach(device_t dev)
|
|
|
|
{
|
|
|
|
struct aml8726_rng_softc *sc = device_get_softc(dev);
|
|
|
|
|
|
|
|
callout_drain(&sc->co);
|
|
|
|
|
|
|
|
bus_release_resources(dev, aml8726_rng_spec, sc->res);
|
|
|
|
|
|
|
|
return (0);
|
|
|
|
}
|
|
|
|
|
|
|
|
static device_method_t aml8726_rng_methods[] = {
|
|
|
|
/* Device interface */
|
|
|
|
DEVMETHOD(device_probe, aml8726_rng_probe),
|
|
|
|
DEVMETHOD(device_attach, aml8726_rng_attach),
|
|
|
|
DEVMETHOD(device_detach, aml8726_rng_detach),
|
|
|
|
|
|
|
|
DEVMETHOD_END
|
|
|
|
};
|
|
|
|
|
|
|
|
static driver_t aml8726_rng_driver = {
|
|
|
|
"rng",
|
|
|
|
aml8726_rng_methods,
|
|
|
|
sizeof(struct aml8726_rng_softc),
|
|
|
|
};
|
|
|
|
|
|
|
|
static devclass_t aml8726_rng_devclass;
|
|
|
|
|
|
|
|
DRIVER_MODULE(aml8726_rng, simplebus, aml8726_rng_driver,
|
|
|
|
aml8726_rng_devclass, 0, 0);
|
|
|
|
MODULE_DEPEND(aml8726_rng, random, 1, 1, 1);
|