1/*- 2 * Copyright (c) 2012 Oleksandr Tymoshenko <gonzo@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 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. 13 * 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 24 * SUCH DAMAGE. 25 */ 26 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: releng/10.3/sys/arm/broadcom/bcm2835/bcm2835_mbox.c 278769 2015-02-14 18:45:43Z loos $"); 29 30#include <sys/param.h> 31#include <sys/systm.h> 32#include <sys/bus.h> 33#include <sys/kernel.h> 34#include <sys/lock.h> 35#include <sys/module.h> 36#include <sys/mutex.h> 37#include <sys/rman.h> 38#include <sys/sema.h> 39#include <machine/bus.h> 40 41#include <dev/ofw/ofw_bus.h> 42#include <dev/ofw/ofw_bus_subr.h> 43 44#include <arm/broadcom/bcm2835/bcm2835_mbox.h> 45 46#include "mbox_if.h" 47 48#define REG_READ 0x00 49#define REG_POL 0x10 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 */ 57 58#define MBOX_MSG(chan, data) (((data) & ~0xf) | ((chan) & 0xf)) 59#define MBOX_CHAN(msg) ((msg) & 0xf) 60#define MBOX_DATA(msg) ((msg) & ~0xf) 61 62#define MBOX_LOCK(sc) do { \ 63 mtx_lock(&(sc)->lock); \ 64} while(0) 65 66#define MBOX_UNLOCK(sc) do { \ 67 mtx_unlock(&(sc)->lock); \ 68} while(0) 69 70#ifdef DEBUG 71#define dprintf(fmt, args...) printf(fmt, ##args) 72#else 73#define dprintf(fmt, args...) 74#endif 75 76struct bcm_mbox_softc { 77 struct mtx lock; 78 struct resource * mem_res; 79 struct resource * irq_res; 80 void* intr_hl; 81 bus_space_tag_t bst; 82 bus_space_handle_t bsh; 83 int msg[BCM2835_MBOX_CHANS]; 84 struct sema sema[BCM2835_MBOX_CHANS]; 85}; 86 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) 91 92static void 93bcm_mbox_intr(void *arg) 94{ 95 struct bcm_mbox_softc *sc = arg; 96 int chan; 97 uint32_t data; 98 uint32_t msg; 99 100 while (!(mbox_read_4(sc, REG_STATUS) & STATUS_EMPTY)) { 101 msg = mbox_read_4(sc, REG_READ); 102 dprintf("bcm_mbox_intr: raw data %08x\n", msg); 103 chan = MBOX_CHAN(msg); 104 data = MBOX_DATA(msg); 105 if (sc->msg[chan]) { 106 printf("bcm_mbox_intr: channel %d oveflow\n", chan); 107 continue; 108 } 109 dprintf("bcm_mbox_intr: chan %d, data %08x\n", chan, data); 110 sc->msg[chan] = msg; 111 sema_post(&sc->sema[chan]); 112 } 113} 114 115static int 116bcm_mbox_probe(device_t dev) 117{ 118 119 if (!ofw_bus_status_okay(dev)) 120 return (ENXIO); 121 122 if (ofw_bus_is_compatible(dev, "broadcom,bcm2835-mbox")) { 123 device_set_desc(dev, "BCM2835 VideoCore Mailbox"); 124 return(BUS_PROBE_DEFAULT); 125 } 126 127 return (ENXIO); 128} 129 130static int 131bcm_mbox_attach(device_t dev) 132{ 133 struct bcm_mbox_softc *sc = device_get_softc(dev); 134 int i; 135 int rid = 0; 136 137 sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE); 138 if (sc->mem_res == NULL) { 139 device_printf(dev, "could not allocate memory resource\n"); 140 return (ENXIO); 141 } 142 143 sc->bst = rman_get_bustag(sc->mem_res); 144 sc->bsh = rman_get_bushandle(sc->mem_res); 145 146 rid = 0; 147 sc->irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, RF_ACTIVE); 148 if (sc->irq_res == NULL) { 149 device_printf(dev, "could not allocate interrupt resource\n"); 150 return (ENXIO); 151 } 152 153 /* Setup and enable the timer */ 154 if (bus_setup_intr(dev, sc->irq_res, INTR_MPSAFE | INTR_TYPE_MISC, 155 NULL, bcm_mbox_intr, sc, &sc->intr_hl) != 0) { 156 bus_release_resource(dev, SYS_RES_IRQ, rid, sc->irq_res); 157 device_printf(dev, "Unable to setup the clock irq handler.\n"); 158 return (ENXIO); 159 } 160 161 mtx_init(&sc->lock, "vcio mbox", NULL, MTX_DEF); 162 for (i = 0; i < BCM2835_MBOX_CHANS; i++) { 163 sc->msg[i] = 0; 164 sema_init(&sc->sema[i], 0, "mbox"); 165 } 166 167 /* Read all pending messages */ 168 while ((mbox_read_4(sc, REG_STATUS) & STATUS_EMPTY) == 0) 169 (void)mbox_read_4(sc, REG_READ); 170 171 mbox_write_4(sc, REG_CONFIG, CONFIG_DATA_IRQ); 172 173 return (0); 174} 175 176/* 177 * Mailbox API 178 */ 179static int 180bcm_mbox_write(device_t dev, int chan, uint32_t data) 181{ 182 int limit = 1000; 183 struct bcm_mbox_softc *sc = device_get_softc(dev); 184 185 dprintf("bcm_mbox_write: chan %d, data %08x\n", chan, data); 186 MBOX_LOCK(sc); 187 while ((mbox_read_4(sc, REG_STATUS) & STATUS_FULL) && --limit) 188 DELAY(5); 189 if (limit == 0) { 190 printf("bcm_mbox_write: STATUS_FULL stuck"); 191 MBOX_UNLOCK(sc); 192 return (EAGAIN); 193 } 194 mbox_write_4(sc, REG_WRITE, MBOX_MSG(chan, data)); 195 MBOX_UNLOCK(sc); 196 197 return (0); 198} 199 200static int 201bcm_mbox_read(device_t dev, int chan, uint32_t *data) 202{ 203 struct bcm_mbox_softc *sc = device_get_softc(dev); 204 205 dprintf("bcm_mbox_read: chan %d\n", chan); 206 MBOX_LOCK(sc); 207 while (sema_trywait(&sc->sema[chan]) == 0) { 208 /* do not unlock sc while waiting for the mbox */ 209 if (sema_timedwait(&sc->sema[chan], 10*hz) == 0) 210 break; 211 printf("timeout sema for chan %d\n", chan); 212 } 213 /* 214 * get data from intr handler, the same channel is never coming 215 * because of holding sc lock. 216 */ 217 *data = MBOX_DATA(sc->msg[chan]); 218 sc->msg[chan] = 0; 219 MBOX_UNLOCK(sc); 220 dprintf("bcm_mbox_read: chan %d, data %08x\n", chan, *data); 221 222 return (0); 223} 224 225static device_method_t bcm_mbox_methods[] = { 226 DEVMETHOD(device_probe, bcm_mbox_probe), 227 DEVMETHOD(device_attach, bcm_mbox_attach), 228 229 DEVMETHOD(mbox_read, bcm_mbox_read), 230 DEVMETHOD(mbox_write, bcm_mbox_write), 231 232 DEVMETHOD_END 233}; 234 235static driver_t bcm_mbox_driver = { 236 "mbox", 237 bcm_mbox_methods, 238 sizeof(struct bcm_mbox_softc), 239}; 240 241static devclass_t bcm_mbox_devclass; 242 243DRIVER_MODULE(mbox, simplebus, bcm_mbox_driver, bcm_mbox_devclass, 0, 0); 244