1 /*- 2 * Copyright (c) 2012, 2013 The FreeBSD Foundation 3 * All rights reserved. 4 * 5 * This software was developed by Oleksandr Rybalko under sponsorship 6 * from the FreeBSD Foundation. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 #include <sys/kernel.h> 36 #include <sys/module.h> 37 #include <sys/time.h> 38 #include <sys/bus.h> 39 #include <sys/resource.h> 40 #include <sys/rman.h> 41 #include <sys/watchdog.h> 42 43 #include <machine/bus.h> 44 #include <machine/intr.h> 45 46 #include <dev/fdt/fdt_common.h> 47 #include <dev/ofw/openfirm.h> 48 #include <dev/ofw/ofw_bus.h> 49 #include <dev/ofw/ofw_bus_subr.h> 50 51 #include <arm/freescale/imx/imx_wdogreg.h> 52 53 struct imx_wdog_softc { 54 struct mtx sc_mtx; 55 device_t sc_dev; 56 bus_space_tag_t sc_bst; 57 bus_space_handle_t sc_bsh; 58 struct resource *sc_res[2]; 59 uint32_t sc_timeout; 60 }; 61 62 static struct resource_spec imx_wdog_spec[] = { 63 { SYS_RES_MEMORY, 0, RF_ACTIVE }, 64 { SYS_RES_IRQ, 0, RF_ACTIVE }, 65 { -1, 0 } 66 }; 67 68 static struct ofw_compat_data compat_data[] = { 69 {"fsl,imx6sx-wdt", 1}, 70 {"fsl,imx6sl-wdt", 1}, 71 {"fsl,imx6q-wdt", 1}, 72 {"fsl,imx53-wdt", 1}, 73 {"fsl,imx51-wdt", 1}, 74 {"fsl,imx50-wdt", 1}, 75 {"fsl,imx35-wdt", 1}, 76 {"fsl,imx27-wdt", 1}, 77 {"fsl,imx25-wdt", 1}, 78 {"fsl,imx21-wdt", 1}, 79 {NULL, 0} 80 }; 81 82 static void imx_watchdog(void *, u_int, int *); 83 static int imx_wdog_probe(device_t); 84 static int imx_wdog_attach(device_t); 85 86 static device_method_t imx_wdog_methods[] = { 87 DEVMETHOD(device_probe, imx_wdog_probe), 88 DEVMETHOD(device_attach, imx_wdog_attach), 89 DEVMETHOD_END 90 }; 91 92 static driver_t imx_wdog_driver = { 93 "imx_wdog", 94 imx_wdog_methods, 95 sizeof(struct imx_wdog_softc), 96 }; 97 static devclass_t imx_wdog_devclass; 98 DRIVER_MODULE(imx_wdog, simplebus, imx_wdog_driver, imx_wdog_devclass, 0, 0); 99 100 #define RD2(_sc, _r) \ 101 bus_space_read_2((_sc)->sc_bst, (_sc)->sc_bsh, (_r)) 102 #define WR2(_sc, _r, _v) \ 103 bus_space_write_2((_sc)->sc_bst, (_sc)->sc_bsh, (_r), (_v)) 104 105 static void 106 imx_watchdog(void *arg, u_int cmd, int *error) 107 { 108 struct imx_wdog_softc *sc; 109 uint16_t reg; 110 int timeout; 111 112 sc = arg; 113 mtx_lock(&sc->sc_mtx); 114 115 /* Refresh counter, since we feels good */ 116 WR2(sc, WDOG_SR_REG, WDOG_SR_STEP1); 117 WR2(sc, WDOG_SR_REG, WDOG_SR_STEP2); 118 119 /* We don't require precession, so "-10" (/1024) is ok */ 120 timeout = (1 << ((cmd & WD_INTERVAL) - 10)) / 1000000; 121 if (timeout > 1 && timeout < 128) { 122 if (timeout != sc->sc_timeout) { 123 device_printf(sc->sc_dev, 124 "WARNING: watchdog can't be disabled!!!"); 125 sc->sc_timeout = timeout; 126 reg = RD2(sc, WDOG_CR_REG); 127 reg &= ~WDOG_CR_WT_MASK; 128 reg |= (timeout << (WDOG_CR_WT_SHIFT + 1)) & 129 WDOG_CR_WT_MASK; 130 WR2(sc, WDOG_CR_REG, reg); 131 /* Refresh counter */ 132 WR2(sc, WDOG_SR_REG, WDOG_SR_STEP1); 133 WR2(sc, WDOG_SR_REG, WDOG_SR_STEP2); 134 *error = 0; 135 } else { 136 *error = EOPNOTSUPP; 137 } 138 } else { 139 device_printf(sc->sc_dev, "Can not be disabled.\n"); 140 *error = EOPNOTSUPP; 141 } 142 mtx_unlock(&sc->sc_mtx); 143 144 } 145 146 static int 147 imx_wdog_probe(device_t dev) 148 { 149 150 if (!ofw_bus_status_okay(dev)) 151 return (ENXIO); 152 153 if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0) 154 return (ENXIO); 155 156 device_set_desc(dev, "Freescale i.MX Watchdog"); 157 return (0); 158 } 159 160 static int 161 imx_wdog_attach(device_t dev) 162 { 163 struct imx_wdog_softc *sc; 164 165 sc = device_get_softc(dev); 166 sc->sc_dev = dev; 167 168 if (bus_alloc_resources(dev, imx_wdog_spec, sc->sc_res)) { 169 device_printf(dev, "could not allocate resources\n"); 170 return (ENXIO); 171 } 172 173 mtx_init(&sc->sc_mtx, device_get_nameunit(dev), "imx_wdt", MTX_DEF); 174 175 sc->sc_dev = dev; 176 sc->sc_bst = rman_get_bustag(sc->sc_res[0]); 177 sc->sc_bsh = rman_get_bushandle(sc->sc_res[0]); 178 179 /* TODO: handle interrupt */ 180 181 EVENTHANDLER_REGISTER(watchdog_list, imx_watchdog, sc, 0); 182 return (0); 183 } 184