2 * Copyright (c) 2012 Oleksandr Tymoshenko <gonzo@freebsd.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include <sys/param.h>
31 #include <sys/systm.h>
33 #include <sys/kernel.h>
35 #include <sys/module.h>
36 #include <sys/mutex.h>
39 #include <machine/bus.h>
41 #include <dev/ofw/ofw_bus.h>
42 #include <dev/ofw/ofw_bus_subr.h>
44 #include <arm/broadcom/bcm2835/bcm2835_mbox.h>
50 #define REG_SENDER 0x14
51 #define REG_STATUS 0x18
52 #define STATUS_FULL 0x80000000
53 #define STATUS_EMPTY 0x40000000
54 #define REG_CONFIG 0x1C
55 #define CONFIG_DATA_IRQ 0x00000001
56 #define REG_WRITE 0x20 /* This is Mailbox 1 address */
58 #define MBOX_MSG(chan, data) (((data) & ~0xf) | ((chan) & 0xf))
59 #define MBOX_CHAN(msg) ((msg) & 0xf)
60 #define MBOX_DATA(msg) ((msg) & ~0xf)
62 #define MBOX_LOCK(sc) do { \
63 mtx_lock(&(sc)->lock); \
66 #define MBOX_UNLOCK(sc) do { \
67 mtx_unlock(&(sc)->lock); \
71 #define dprintf(fmt, args...) printf(fmt, ##args)
73 #define dprintf(fmt, args...)
76 struct bcm_mbox_softc {
78 struct resource * mem_res;
79 struct resource * irq_res;
82 bus_space_handle_t bsh;
83 int msg[BCM2835_MBOX_CHANS];
84 struct sema sema[BCM2835_MBOX_CHANS];
87 #define mbox_read_4(sc, reg) \
88 bus_space_read_4((sc)->bst, (sc)->bsh, reg)
89 #define mbox_write_4(sc, reg, val) \
90 bus_space_write_4((sc)->bst, (sc)->bsh, reg, val)
93 bcm_mbox_read_msg(struct bcm_mbox_softc *sc, int *ochan)
99 msg = mbox_read_4(sc, REG_READ);
100 dprintf("bcm_mbox_intr: raw data %08x\n", msg);
101 chan = MBOX_CHAN(msg);
102 data = MBOX_DATA(msg);
104 printf("bcm_mbox_intr: channel %d oveflow\n", chan);
107 dprintf("bcm_mbox_intr: chan %d, data %08x\n", chan, data);
117 bcm_mbox_intr(void *arg)
119 struct bcm_mbox_softc *sc = arg;
122 while (!(mbox_read_4(sc, REG_STATUS) & STATUS_EMPTY))
123 if (bcm_mbox_read_msg(sc, &chan) == 0)
124 sema_post(&sc->sema[chan]);
128 bcm_mbox_probe(device_t dev)
131 if (!ofw_bus_status_okay(dev))
134 if (ofw_bus_is_compatible(dev, "broadcom,bcm2835-mbox")) {
135 device_set_desc(dev, "BCM2835 VideoCore Mailbox");
136 return(BUS_PROBE_DEFAULT);
143 bcm_mbox_attach(device_t dev)
145 struct bcm_mbox_softc *sc = device_get_softc(dev);
149 sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
150 if (sc->mem_res == NULL) {
151 device_printf(dev, "could not allocate memory resource\n");
155 sc->bst = rman_get_bustag(sc->mem_res);
156 sc->bsh = rman_get_bushandle(sc->mem_res);
159 sc->irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, RF_ACTIVE);
160 if (sc->irq_res == NULL) {
161 device_printf(dev, "could not allocate interrupt resource\n");
165 /* Setup and enable the timer */
166 if (bus_setup_intr(dev, sc->irq_res, INTR_MPSAFE | INTR_TYPE_MISC,
167 NULL, bcm_mbox_intr, sc, &sc->intr_hl) != 0) {
168 bus_release_resource(dev, SYS_RES_IRQ, rid, sc->irq_res);
169 device_printf(dev, "Unable to setup the clock irq handler.\n");
173 mtx_init(&sc->lock, "vcio mbox", NULL, MTX_DEF);
174 for (i = 0; i < BCM2835_MBOX_CHANS; i++) {
176 sema_init(&sc->sema[i], 0, "mbox");
179 /* Read all pending messages */
180 while ((mbox_read_4(sc, REG_STATUS) & STATUS_EMPTY) == 0)
181 (void)mbox_read_4(sc, REG_READ);
183 mbox_write_4(sc, REG_CONFIG, CONFIG_DATA_IRQ);
192 bcm_mbox_write(device_t dev, int chan, uint32_t data)
195 struct bcm_mbox_softc *sc = device_get_softc(dev);
197 dprintf("bcm_mbox_write: chan %d, data %08x\n", chan, data);
199 while ((mbox_read_4(sc, REG_STATUS) & STATUS_FULL) && --limit)
202 printf("bcm_mbox_write: STATUS_FULL stuck");
206 mbox_write_4(sc, REG_WRITE, MBOX_MSG(chan, data));
213 bcm_mbox_read(device_t dev, int chan, uint32_t *data)
215 struct bcm_mbox_softc *sc = device_get_softc(dev);
218 dprintf("bcm_mbox_read: chan %d\n", chan);
223 while (sema_trywait(&sc->sema[chan]) == 0) {
224 /* do not unlock sc while waiting for the mbox */
225 if (sema_timedwait(&sc->sema[chan], 10*hz) == 0)
227 printf("timeout sema for chan %d\n", chan);
231 /* Wait for a message */
232 while ((mbox_read_4(sc, REG_STATUS) & STATUS_EMPTY))
234 /* Read the message */
235 if (bcm_mbox_read_msg(sc, &read_chan) != 0) {
239 } while (read_chan != chan);
242 * get data from intr handler, the same channel is never coming
243 * because of holding sc lock.
245 *data = MBOX_DATA(sc->msg[chan]);
249 dprintf("bcm_mbox_read: chan %d, data %08x\n", chan, *data);
254 static device_method_t bcm_mbox_methods[] = {
255 DEVMETHOD(device_probe, bcm_mbox_probe),
256 DEVMETHOD(device_attach, bcm_mbox_attach),
258 DEVMETHOD(mbox_read, bcm_mbox_read),
259 DEVMETHOD(mbox_write, bcm_mbox_write),
264 static driver_t bcm_mbox_driver = {
267 sizeof(struct bcm_mbox_softc),
270 static devclass_t bcm_mbox_devclass;
272 DRIVER_MODULE(mbox, simplebus, bcm_mbox_driver, bcm_mbox_devclass, 0, 0);