1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2012, 2013 The FreeBSD Foundation 5 * All rights reserved. 6 * 7 * This software was developed by Oleksandr Rybalko under sponsorship 8 * from the FreeBSD Foundation. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/kernel.h> 38 #include <sys/module.h> 39 #include <sys/time.h> 40 #include <sys/bus.h> 41 #include <sys/resource.h> 42 #include <sys/rman.h> 43 #include <sys/watchdog.h> 44 45 #include <machine/bus.h> 46 #include <machine/intr.h> 47 48 #include <dev/ofw/openfirm.h> 49 #include <dev/ofw/ofw_bus.h> 50 #include <dev/ofw/ofw_bus_subr.h> 51 52 #include <arm/freescale/imx/imx_wdogreg.h> 53 54 struct imx_wdog_softc { 55 struct mtx sc_mtx; 56 device_t sc_dev; 57 bus_space_tag_t sc_bst; 58 bus_space_handle_t sc_bsh; 59 struct resource *sc_res[2]; 60 uint32_t sc_timeout; 61 }; 62 63 static struct resource_spec imx_wdog_spec[] = { 64 { SYS_RES_MEMORY, 0, RF_ACTIVE }, 65 { SYS_RES_IRQ, 0, RF_ACTIVE }, 66 { -1, 0 } 67 }; 68 69 static struct ofw_compat_data compat_data[] = { 70 {"fsl,imx6sx-wdt", 1}, 71 {"fsl,imx6sl-wdt", 1}, 72 {"fsl,imx6q-wdt", 1}, 73 {"fsl,imx53-wdt", 1}, 74 {"fsl,imx51-wdt", 1}, 75 {"fsl,imx50-wdt", 1}, 76 {"fsl,imx35-wdt", 1}, 77 {"fsl,imx27-wdt", 1}, 78 {"fsl,imx25-wdt", 1}, 79 {"fsl,imx21-wdt", 1}, 80 {NULL, 0} 81 }; 82 83 static void imx_watchdog(void *, u_int, int *); 84 static int imx_wdog_probe(device_t); 85 static int imx_wdog_attach(device_t); 86 87 static device_method_t imx_wdog_methods[] = { 88 DEVMETHOD(device_probe, imx_wdog_probe), 89 DEVMETHOD(device_attach, imx_wdog_attach), 90 DEVMETHOD_END 91 }; 92 93 static driver_t imx_wdog_driver = { 94 "imx_wdog", 95 imx_wdog_methods, 96 sizeof(struct imx_wdog_softc), 97 }; 98 static devclass_t imx_wdog_devclass; 99 DRIVER_MODULE(imx_wdog, simplebus, imx_wdog_driver, imx_wdog_devclass, 0, 0); 100 101 #define RD2(_sc, _r) \ 102 bus_space_read_2((_sc)->sc_bst, (_sc)->sc_bsh, (_r)) 103 #define WR2(_sc, _r, _v) \ 104 bus_space_write_2((_sc)->sc_bst, (_sc)->sc_bsh, (_r), (_v)) 105 106 static void 107 imx_watchdog(void *arg, u_int cmd, int *error) 108 { 109 struct imx_wdog_softc *sc; 110 uint16_t reg; 111 u_int timeout; 112 113 sc = arg; 114 mtx_lock(&sc->sc_mtx); 115 if (cmd == 0) { 116 if (bootverbose) 117 device_printf(sc->sc_dev, "Can not be disabled.\n"); 118 *error = EOPNOTSUPP; 119 } else { 120 timeout = (u_int)((1ULL << (cmd & WD_INTERVAL)) / 1000000000U); 121 if (timeout > 1 && timeout < 128) { 122 if (timeout != sc->sc_timeout) { 123 sc->sc_timeout = timeout; 124 reg = RD2(sc, WDOG_CR_REG); 125 reg &= ~WDOG_CR_WT_MASK; 126 reg |= (timeout << (WDOG_CR_WT_SHIFT + 1)) & 127 WDOG_CR_WT_MASK; 128 WR2(sc, WDOG_CR_REG, reg | WDOG_CR_WDE); 129 } 130 /* Refresh counter */ 131 WR2(sc, WDOG_SR_REG, WDOG_SR_STEP1); 132 WR2(sc, WDOG_SR_REG, WDOG_SR_STEP2); 133 *error = 0; 134 } 135 } 136 mtx_unlock(&sc->sc_mtx); 137 } 138 139 static int 140 imx_wdog_probe(device_t dev) 141 { 142 143 if (!ofw_bus_status_okay(dev)) 144 return (ENXIO); 145 146 if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0) 147 return (ENXIO); 148 149 device_set_desc(dev, "Freescale i.MX Watchdog"); 150 return (0); 151 } 152 153 static int 154 imx_wdog_attach(device_t dev) 155 { 156 struct imx_wdog_softc *sc; 157 158 sc = device_get_softc(dev); 159 sc->sc_dev = dev; 160 161 if (bus_alloc_resources(dev, imx_wdog_spec, sc->sc_res)) { 162 device_printf(dev, "could not allocate resources\n"); 163 return (ENXIO); 164 } 165 166 mtx_init(&sc->sc_mtx, device_get_nameunit(dev), "imx_wdt", MTX_DEF); 167 168 sc->sc_dev = dev; 169 sc->sc_bst = rman_get_bustag(sc->sc_res[0]); 170 sc->sc_bsh = rman_get_bushandle(sc->sc_res[0]); 171 172 /* TODO: handle interrupt */ 173 174 EVENTHANDLER_REGISTER(watchdog_list, imx_watchdog, sc, 0); 175 return (0); 176 } 177