bcm2835_mbox.c revision 278608
1249268Sglebius/*- 2249268Sglebius * Copyright (c) 2012 Oleksandr Tymoshenko <gonzo@freebsd.org> 3249268Sglebius * All rights reserved. 4249268Sglebius * 5249268Sglebius * Redistribution and use in source and binary forms, with or without 6249268Sglebius * modification, are permitted provided that the following conditions 7249268Sglebius * are met: 8249268Sglebius * 1. Redistributions of source code must retain the above copyright 9249268Sglebius * notice, this list of conditions and the following disclaimer. 10249268Sglebius * 2. Redistributions in binary form must reproduce the above copyright 11249268Sglebius * notice, this list of conditions and the following disclaimer in the 12249268Sglebius * documentation and/or other materials provided with the distribution. 13249268Sglebius * 14249268Sglebius * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15249268Sglebius * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16249268Sglebius * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17249268Sglebius * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18249268Sglebius * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19249268Sglebius * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20249268Sglebius * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21249268Sglebius * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22249268Sglebius * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23249268Sglebius * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24249268Sglebius * SUCH DAMAGE. 25249268Sglebius */ 26249268Sglebius 27249268Sglebius#include <sys/cdefs.h> 28249268Sglebius__FBSDID("$FreeBSD: stable/10/sys/arm/broadcom/bcm2835/bcm2835_mbox.c 278608 2015-02-12 00:25:33Z ian $"); 29249268Sglebius 30249268Sglebius#include <sys/param.h> 31249268Sglebius#include <sys/systm.h> 32249268Sglebius#include <sys/bus.h> 33249268Sglebius#include <sys/kernel.h> 34249268Sglebius#include <sys/module.h> 35249268Sglebius#include <sys/malloc.h> 36249268Sglebius#include <sys/rman.h> 37249268Sglebius#include <sys/sema.h> 38249268Sglebius#include <sys/timeet.h> 39249268Sglebius#include <sys/timetc.h> 40252434Skib#include <sys/watchdog.h> 41252434Skib#include <machine/bus.h> 42252434Skib#include <machine/cpu.h> 43252434Skib#include <machine/intr.h> 44252434Skib 45252434Skib#include <dev/fdt/fdt_common.h> 46252434Skib#include <dev/ofw/openfirm.h> 47252434Skib#include <dev/ofw/ofw_bus.h> 48252434Skib#include <dev/ofw/ofw_bus_subr.h> 49252434Skib 50252434Skib#include <machine/bus.h> 51252434Skib#include <machine/fdt.h> 52252434Skib 53252434Skib#include <arm/broadcom/bcm2835/bcm2835_mbox.h> 54252434Skib 55252434Skib#include "mbox_if.h" 56252434Skib 57252434Skib#define REG_READ 0x00 58252434Skib#define REG_POL 0x10 59252434Skib#define REG_SENDER 0x14 60252434Skib#define REG_STATUS 0x18 61252434Skib#define STATUS_FULL 0x80000000 62252434Skib#define STATUS_EMPTY 0x40000000 63252434Skib#define REG_CONFIG 0x1C 64252434Skib#define CONFIG_DATA_IRQ 0x00000001 65252434Skib#define REG_WRITE 0x20 /* This is Mailbox 1 address */ 66252434Skib 67252434Skib#define MBOX_MSG(chan, data) (((data) & ~0xf) | ((chan) & 0xf)) 68252434Skib#define MBOX_CHAN(msg) ((msg) & 0xf) 69252434Skib#define MBOX_DATA(msg) ((msg) & ~0xf) 70252434Skib 71252434Skib#define MBOX_LOCK(sc) do { \ 72252434Skib mtx_lock(&(sc)->lock); \ 73252434Skib} while(0) 74252434Skib 75252434Skib#define MBOX_UNLOCK(sc) do { \ 76252434Skib mtx_unlock(&(sc)->lock); \ 77252434Skib} while(0) 78252434Skib 79252434Skib#undef DEBUG 80249268Sglebius#ifdef DEBUG 81249268Sglebius#define dprintf(fmt, args...) printf(fmt, ##args) 82249268Sglebius#else 83249268Sglebius#define dprintf(fmt, args...) 84249268Sglebius#endif 85249268Sglebius 86249268Sglebiusstruct bcm_mbox_softc { 87249268Sglebius struct mtx lock; 88249268Sglebius struct resource * mem_res; 89249268Sglebius struct resource * irq_res; 90249268Sglebius void* intr_hl; 91249268Sglebius bus_space_tag_t bst; 92249268Sglebius bus_space_handle_t bsh; 93249268Sglebius int msg[BCM2835_MBOX_CHANS]; 94249268Sglebius struct sema sema[BCM2835_MBOX_CHANS]; 95}; 96 97#define mbox_read_4(sc, reg) \ 98 bus_space_read_4((sc)->bst, (sc)->bsh, reg) 99#define mbox_write_4(sc, reg, val) \ 100 bus_space_write_4((sc)->bst, (sc)->bsh, reg, val) 101 102static void 103bcm_mbox_intr(void *arg) 104{ 105 struct bcm_mbox_softc *sc = arg; 106 int chan; 107 uint32_t data; 108 uint32_t msg; 109 110 while (!(mbox_read_4(sc, REG_STATUS) & STATUS_EMPTY)) { 111 msg = mbox_read_4(sc, REG_READ); 112 dprintf("bcm_mbox_intr: raw data %08x\n", msg); 113 chan = MBOX_CHAN(msg); 114 data = MBOX_DATA(msg); 115 if (sc->msg[chan]) { 116 printf("bcm_mbox_intr: channel %d oveflow\n", chan); 117 continue; 118 } 119 dprintf("bcm_mbox_intr: chan %d, data %08x\n", chan, data); 120 sc->msg[chan] = msg; 121 sema_post(&sc->sema[chan]); 122 } 123} 124 125static int 126bcm_mbox_probe(device_t dev) 127{ 128 129 if (!ofw_bus_status_okay(dev)) 130 return (ENXIO); 131 132 if (ofw_bus_is_compatible(dev, "broadcom,bcm2835-mbox")) { 133 device_set_desc(dev, "BCM2835 VideoCore Mailbox"); 134 return(BUS_PROBE_DEFAULT); 135 } 136 137 return (ENXIO); 138} 139 140static int 141bcm_mbox_attach(device_t dev) 142{ 143 struct bcm_mbox_softc *sc = device_get_softc(dev); 144 int i; 145 int rid = 0; 146 147 sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE); 148 if (sc->mem_res == NULL) { 149 device_printf(dev, "could not allocate memory resource\n"); 150 return (ENXIO); 151 } 152 153 sc->bst = rman_get_bustag(sc->mem_res); 154 sc->bsh = rman_get_bushandle(sc->mem_res); 155 156 rid = 0; 157 sc->irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, RF_ACTIVE); 158 if (sc->irq_res == NULL) { 159 device_printf(dev, "could not allocate interrupt resource\n"); 160 return (ENXIO); 161 } 162 163 /* Setup and enable the timer */ 164 if (bus_setup_intr(dev, sc->irq_res, INTR_MPSAFE | INTR_TYPE_MISC, 165 NULL, bcm_mbox_intr, sc, &sc->intr_hl) != 0) { 166 bus_release_resource(dev, SYS_RES_IRQ, rid, sc->irq_res); 167 device_printf(dev, "Unable to setup the clock irq handler.\n"); 168 return (ENXIO); 169 } 170 171 mtx_init(&sc->lock, "vcio mbox", NULL, MTX_DEF); 172 for (i = 0; i < BCM2835_MBOX_CHANS; i++) { 173 sc->msg[i] = 0; 174 sema_init(&sc->sema[i], 0, "mbox"); 175 } 176 177 /* Read all pending messages */ 178 while ((mbox_read_4(sc, REG_STATUS) & STATUS_EMPTY) == 0) 179 (void)mbox_read_4(sc, REG_READ); 180 181 mbox_write_4(sc, REG_CONFIG, CONFIG_DATA_IRQ); 182 183 return (0); 184} 185 186/* 187 * Mailbox API 188 */ 189static int 190bcm_mbox_write(device_t dev, int chan, uint32_t data) 191{ 192 int limit = 20000; 193 struct bcm_mbox_softc *sc = device_get_softc(dev); 194 195 dprintf("bcm_mbox_write: chan %d, data %08x\n", chan, data); 196 MBOX_LOCK(sc); 197 198 while ((mbox_read_4(sc, REG_STATUS) & STATUS_FULL) && limit--) { 199 DELAY(2); 200 } 201 202 if (limit == 0) { 203 printf("bcm_mbox_write: STATUS_FULL stuck"); 204 MBOX_UNLOCK(sc); 205 return (EAGAIN); 206 } 207 208 mbox_write_4(sc, REG_WRITE, MBOX_MSG(chan, data)); 209 210 MBOX_UNLOCK(sc); 211 return (0); 212} 213 214static int 215bcm_mbox_read(device_t dev, int chan, uint32_t *data) 216{ 217 struct bcm_mbox_softc *sc = device_get_softc(dev); 218 219 dprintf("bcm_mbox_read: chan %d\n", chan); 220 MBOX_LOCK(sc); 221 while (sema_trywait(&sc->sema[chan]) == 0) { 222 /* do not unlock sc while waiting for the mbox */ 223 if (sema_timedwait(&sc->sema[chan], 10*hz) == 0) 224 break; 225 printf("timeout sema for chan %d\n", chan); 226 } 227 /* 228 * get data from intr handler, the same channel is never coming 229 * because of holding sc lock. 230 */ 231 *data = MBOX_DATA(sc->msg[chan]); 232 sc->msg[chan] = 0; 233 MBOX_UNLOCK(sc); 234 dprintf("bcm_mbox_read: chan %d, data %08x\n", chan, *data); 235 236 return (0); 237} 238 239static device_method_t bcm_mbox_methods[] = { 240 DEVMETHOD(device_probe, bcm_mbox_probe), 241 DEVMETHOD(device_attach, bcm_mbox_attach), 242 243 DEVMETHOD(mbox_read, bcm_mbox_read), 244 DEVMETHOD(mbox_write, bcm_mbox_write), 245 246 DEVMETHOD_END 247}; 248 249static driver_t bcm_mbox_driver = { 250 "mbox", 251 bcm_mbox_methods, 252 sizeof(struct bcm_mbox_softc), 253}; 254 255static devclass_t bcm_mbox_devclass; 256 257DRIVER_MODULE(mbox, simplebus, bcm_mbox_driver, bcm_mbox_devclass, 0, 0); 258 259