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/*-
* Copyright (c) 2012 Oleksandr Tymoshenko <gonzo@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.
*/
#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/mutex.h>
#include <sys/rman.h>
#include <sys/sema.h>
#include <machine/bus.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <arm/broadcom/bcm2835/bcm2835_mbox.h>
#include "mbox_if.h"
#define REG_READ 0x00
#define REG_POL 0x10
#define REG_SENDER 0x14
#define REG_STATUS 0x18
#define STATUS_FULL 0x80000000
#define STATUS_EMPTY 0x40000000
#define REG_CONFIG 0x1C
#define CONFIG_DATA_IRQ 0x00000001
#define REG_WRITE 0x20 /* This is Mailbox 1 address */
#define MBOX_MSG(chan, data) (((data) & ~0xf) | ((chan) & 0xf))
#define MBOX_CHAN(msg) ((msg) & 0xf)
#define MBOX_DATA(msg) ((msg) & ~0xf)
#define MBOX_LOCK(sc) do { \
mtx_lock(&(sc)->lock); \
} while(0)
#define MBOX_UNLOCK(sc) do { \
mtx_unlock(&(sc)->lock); \
} while(0)
#ifdef DEBUG
#define dprintf(fmt, args...) printf(fmt, ##args)
#else
#define dprintf(fmt, args...)
#endif
struct bcm_mbox_softc {
struct mtx lock;
struct resource * mem_res;
struct resource * irq_res;
void* intr_hl;
bus_space_tag_t bst;
bus_space_handle_t bsh;
int msg[BCM2835_MBOX_CHANS];
struct sema sema[BCM2835_MBOX_CHANS];
};
#define mbox_read_4(sc, reg) \
bus_space_read_4((sc)->bst, (sc)->bsh, reg)
#define mbox_write_4(sc, reg, val) \
bus_space_write_4((sc)->bst, (sc)->bsh, reg, val)
static void
bcm_mbox_intr(void *arg)
{
struct bcm_mbox_softc *sc = arg;
int chan;
uint32_t data;
uint32_t msg;
while (!(mbox_read_4(sc, REG_STATUS) & STATUS_EMPTY)) {
msg = mbox_read_4(sc, REG_READ);
dprintf("bcm_mbox_intr: raw data %08x\n", msg);
chan = MBOX_CHAN(msg);
data = MBOX_DATA(msg);
if (sc->msg[chan]) {
printf("bcm_mbox_intr: channel %d oveflow\n", chan);
continue;
}
dprintf("bcm_mbox_intr: chan %d, data %08x\n", chan, data);
sc->msg[chan] = msg;
sema_post(&sc->sema[chan]);
}
}
static int
bcm_mbox_probe(device_t dev)
{
if (!ofw_bus_status_okay(dev))
return (ENXIO);
if (ofw_bus_is_compatible(dev, "broadcom,bcm2835-mbox")) {
device_set_desc(dev, "BCM2835 VideoCore Mailbox");
return(BUS_PROBE_DEFAULT);
}
return (ENXIO);
}
static int
bcm_mbox_attach(device_t dev)
{
struct bcm_mbox_softc *sc = device_get_softc(dev);
int i;
int rid = 0;
sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
if (sc->mem_res == NULL) {
device_printf(dev, "could not allocate memory resource\n");
return (ENXIO);
}
sc->bst = rman_get_bustag(sc->mem_res);
sc->bsh = rman_get_bushandle(sc->mem_res);
rid = 0;
sc->irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, RF_ACTIVE);
if (sc->irq_res == NULL) {
device_printf(dev, "could not allocate interrupt resource\n");
return (ENXIO);
}
/* Setup and enable the timer */
if (bus_setup_intr(dev, sc->irq_res, INTR_MPSAFE | INTR_TYPE_MISC,
NULL, bcm_mbox_intr, sc, &sc->intr_hl) != 0) {
bus_release_resource(dev, SYS_RES_IRQ, rid, sc->irq_res);
device_printf(dev, "Unable to setup the clock irq handler.\n");
return (ENXIO);
}
mtx_init(&sc->lock, "vcio mbox", NULL, MTX_DEF);
for (i = 0; i < BCM2835_MBOX_CHANS; i++) {
sc->msg[i] = 0;
sema_init(&sc->sema[i], 0, "mbox");
}
/* Read all pending messages */
while ((mbox_read_4(sc, REG_STATUS) & STATUS_EMPTY) == 0)
(void)mbox_read_4(sc, REG_READ);
mbox_write_4(sc, REG_CONFIG, CONFIG_DATA_IRQ);
return (0);
}
/*
* Mailbox API
*/
static int
bcm_mbox_write(device_t dev, int chan, uint32_t data)
{
int limit = 1000;
struct bcm_mbox_softc *sc = device_get_softc(dev);
dprintf("bcm_mbox_write: chan %d, data %08x\n", chan, data);
MBOX_LOCK(sc);
while ((mbox_read_4(sc, REG_STATUS) & STATUS_FULL) && --limit)
DELAY(5);
if (limit == 0) {
printf("bcm_mbox_write: STATUS_FULL stuck");
MBOX_UNLOCK(sc);
return (EAGAIN);
}
mbox_write_4(sc, REG_WRITE, MBOX_MSG(chan, data));
MBOX_UNLOCK(sc);
return (0);
}
static int
bcm_mbox_read(device_t dev, int chan, uint32_t *data)
{
struct bcm_mbox_softc *sc = device_get_softc(dev);
dprintf("bcm_mbox_read: chan %d\n", chan);
MBOX_LOCK(sc);
while (sema_trywait(&sc->sema[chan]) == 0) {
/* do not unlock sc while waiting for the mbox */
if (sema_timedwait(&sc->sema[chan], 10*hz) == 0)
break;
printf("timeout sema for chan %d\n", chan);
}
/*
* get data from intr handler, the same channel is never coming
* because of holding sc lock.
*/
*data = MBOX_DATA(sc->msg[chan]);
sc->msg[chan] = 0;
MBOX_UNLOCK(sc);
dprintf("bcm_mbox_read: chan %d, data %08x\n", chan, *data);
return (0);
}
static device_method_t bcm_mbox_methods[] = {
DEVMETHOD(device_probe, bcm_mbox_probe),
DEVMETHOD(device_attach, bcm_mbox_attach),
DEVMETHOD(mbox_read, bcm_mbox_read),
DEVMETHOD(mbox_write, bcm_mbox_write),
DEVMETHOD_END
};
static driver_t bcm_mbox_driver = {
"mbox",
bcm_mbox_methods,
sizeof(struct bcm_mbox_softc),
};
static devclass_t bcm_mbox_devclass;
DRIVER_MODULE(mbox, simplebus, bcm_mbox_driver, bcm_mbox_devclass, 0, 0);
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