freebsd-dev/sys/mips/cavium/octeon_rnd.c
Nathan Whitehorn 5543a1b98e Devices that rely on hints or identify routines for discovery need to
return BUS_PROBE_NOWILDCARD from their probe routines to avoid claiming
wildcard devices on their parent bus. Do a sweep through the MIPS tree.

MFC after: 2 weeks
2013-10-29 14:07:31 +00:00

133 lines
3.6 KiB
C

/*-
* Copyright (c) 2010 Juli Mallett <jmallett@FreeBSD.org>
* 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.
*
* $FreeBSD$
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/clock.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/random.h>
#include <contrib/octeon-sdk/cvmx.h>
#include <contrib/octeon-sdk/cvmx-rng.h>
#define OCTEON_RND_WORDS 2
struct octeon_rnd_softc {
uint64_t sc_entropy[OCTEON_RND_WORDS];
struct callout sc_callout;
};
static void octeon_rnd_identify(driver_t *drv, device_t parent);
static int octeon_rnd_attach(device_t dev);
static int octeon_rnd_probe(device_t dev);
static int octeon_rnd_detach(device_t dev);
static void octeon_rnd_harvest(void *);
static device_method_t octeon_rnd_methods[] = {
/* Device interface */
DEVMETHOD(device_identify, octeon_rnd_identify),
DEVMETHOD(device_probe, octeon_rnd_probe),
DEVMETHOD(device_attach, octeon_rnd_attach),
DEVMETHOD(device_detach, octeon_rnd_detach),
{ 0, 0 }
};
static driver_t octeon_rnd_driver = {
"rnd",
octeon_rnd_methods,
sizeof (struct octeon_rnd_softc)
};
static devclass_t octeon_rnd_devclass;
DRIVER_MODULE(rnd, nexus, octeon_rnd_driver, octeon_rnd_devclass, 0, 0);
static void
octeon_rnd_identify(driver_t *drv, device_t parent)
{
BUS_ADD_CHILD(parent, 0, "rnd", 0);
}
static int
octeon_rnd_probe(device_t dev)
{
if (device_get_unit(dev) != 0)
return (ENXIO);
device_set_desc(dev, "Cavium Octeon Random Number Generator");
return (BUS_PROBE_NOWILDCARD);
}
static int
octeon_rnd_attach(device_t dev)
{
struct octeon_rnd_softc *sc;
sc = device_get_softc(dev);
callout_init(&sc->sc_callout, CALLOUT_MPSAFE);
callout_reset(&sc->sc_callout, hz * 5, octeon_rnd_harvest, sc);
cvmx_rng_enable();
return (0);
}
static int
octeon_rnd_detach(device_t dev)
{
struct octeon_rnd_softc *sc;
sc = device_get_softc(dev);
callout_stop(&sc->sc_callout);
return (0);
}
static void
octeon_rnd_harvest(void *arg)
{
struct octeon_rnd_softc *sc;
unsigned i;
sc = arg;
for (i = 0; i < OCTEON_RND_WORDS; i++)
sc->sc_entropy[i] = cvmx_rng_get_random64();
random_harvest(sc->sc_entropy, sizeof sc->sc_entropy,
(sizeof(sc->sc_entropy)*8)/2, RANDOM_PURE_OCTEON);
callout_reset(&sc->sc_callout, hz * 5, octeon_rnd_harvest, sc);
}