/*- * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2019 Andriy Gapon * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include #include #include #include #include #include #include #include #include #include #include struct itwd_softc { eventhandler_tag wd_ev; void *intr_handle; struct resource *intr_res; int intr_rid; }; static void wd_func(void *priv, u_int cmd, int *error) { device_t dev = priv; uint64_t timeout; uint8_t val; if (cmd != 0) { cmd &= WD_INTERVAL; /* * Convert the requested timeout to seconds. * If the timeout is smaller than the minimal supported value * then set it to the minimum. * TODO This hardware actually supports 64ms resolution * when bit 5 of 0x72 is set. Switch to that resolution when * needed. */ if (cmd >= WD_TO_1SEC) timeout = (uint64_t)1 << (cmd - WD_TO_1SEC); else timeout = 1; /* TODO If timeout is greater than maximum value * that can be specified in seconds, we should * switch the timer to minutes mode by clearing * bit 7 of 0x72 (ensure that bit 5 is also cleared). * * For now, just disable the timer to honor the * watchdog(9) protocol. * * XXX The timeout actually can be up to 65535 units * as it is set via two registers 0x73, LSB, and 0x74, * MSB. But it is not clear what the protocol for writing * those two registers is. */ if (timeout <= UINT8_MAX) { val = timeout; *error = 0; } else { /* error left unchanged */ val = 0; } } else { val = 0; } #ifdef DIAGNOSTIC if (bootverbose) device_printf(dev, "setting timeout to %d\n", val); #endif superio_write(dev, 0x73, val); if (superio_read(dev, 0x73) != val) superio_write(dev, 0x73, val); } static void itwd_intr(void *cookie) { device_t dev = cookie; uint8_t val; val = superio_read(dev, 0x71); if (bootverbose) device_printf(dev, "got interrupt, wdt status = %d\n", val & 1); superio_write(dev, 0x71, val & ~((uint8_t)0x01)); } static int itwd_probe(device_t dev) { if (superio_vendor(dev) != SUPERIO_VENDOR_ITE) return (ENXIO); if (superio_get_type(dev) != SUPERIO_DEV_WDT) return (ENXIO); device_set_desc(dev, "Watchdog Timer on ITE SuperIO"); return (BUS_PROBE_DEFAULT); } static int itwd_attach(device_t dev) { struct itwd_softc *sc = device_get_softc(dev); int irq = 0; int nmi = 0; int error; /* First, reset the timeout, just in case. */ superio_write(dev, 0x74, 0); superio_write(dev, 0x73, 0); TUNABLE_INT_FETCH("dev.itwd.irq", &irq); TUNABLE_INT_FETCH("dev.itwd.nmi", &nmi); if (irq < 0 || irq > 15) { device_printf(dev, "Ignoring invalid IRQ value %d\n", irq); irq = 0; } if (irq == 0 && nmi) { device_printf(dev, "Ignoring NMI mode if IRQ is not set\n"); nmi = 0; } /* * NB: if the interrupt has been configured for the NMI delivery, * then it is not available for the regular interrupt allocation. * Thus, we configure the hardware to generate the interrupt, * but do not attempt to allocate and setup it as a regular * interrupt. */ if (irq != 0 && !nmi) { sc->intr_rid = 0; bus_set_resource(dev, SYS_RES_IRQ, sc->intr_rid, irq, 1); sc->intr_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &sc->intr_rid, RF_ACTIVE); if (sc->intr_res == NULL) { device_printf(dev, "unable to map interrupt\n"); return (ENXIO); } error = bus_setup_intr(dev, sc->intr_res, INTR_TYPE_MISC | INTR_MPSAFE, NULL, itwd_intr, dev, &sc->intr_handle); if (error != 0) { bus_release_resource(dev, SYS_RES_IRQ, sc->intr_rid, sc->intr_res); device_printf(dev, "Unable to setup irq: error %d\n", error); return (ENXIO); } } if (irq != 0) { device_printf(dev, "Using IRQ%d to signal timeout\n", irq); } else { /* System reset via KBRST. */ irq = 0x40; device_printf(dev, "Configured for system reset on timeout\n"); } superio_write(dev, 0x71, 0); superio_write(dev, 0x72, 0x80 | (uint8_t)irq); sc->wd_ev = EVENTHANDLER_REGISTER(watchdog_list, wd_func, dev, 0); return (0); } static int itwd_detach(device_t dev) { struct itwd_softc *sc = device_get_softc(dev); int dummy; if (sc->wd_ev != NULL) EVENTHANDLER_DEREGISTER(watchdog_list, sc->wd_ev); wd_func(dev, 0, &dummy); if (sc->intr_handle) bus_teardown_intr(dev, sc->intr_res, sc->intr_handle); if (sc->intr_res) bus_release_resource(dev, SYS_RES_IRQ, sc->intr_rid, sc->intr_res); return (0); } static device_method_t itwd_methods[] = { /* Methods from the device interface */ DEVMETHOD(device_probe, itwd_probe), DEVMETHOD(device_attach, itwd_attach), DEVMETHOD(device_detach, itwd_detach), /* Terminate method list */ { 0, 0 } }; static driver_t itwd_driver = { "itwd", itwd_methods, sizeof (struct itwd_softc) }; static devclass_t itwd_devclass; DRIVER_MODULE(itwd, superio, itwd_driver, itwd_devclass, NULL, NULL); MODULE_DEPEND(itwd, superio, 1, 1, 1); MODULE_VERSION(itwd, 1);