--- /dev/null
+/* $OpenBSD: gpiorestart.c,v 1.1 2022/06/09 12:13:56 kettenis Exp $ */
+/*
+ * Copyright (c) 2022 Mark Kettenis
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/device.h>
+#include <sys/malloc.h>
+
+#include <machine/bus.h>
+#include <machine/fdt.h>
+
+#include <dev/ofw/openfirm.h>
+#include <dev/ofw/ofw_gpio.h>
+#include <dev/ofw/fdt.h>
+
+extern void (*cpuresetfn)(void);
+
+struct gpiorestart_softc {
+ struct device sc_dev;
+ uint32_t *sc_gpio;
+ uint32_t sc_active_delay;
+ uint32_t sc_inactive_delay;
+ uint32_t sc_wait_delay;
+};
+
+int gpiorestart_match(struct device *, void *, void *);
+void gpiorestart_attach(struct device *, struct device *, void *);
+
+const struct cfattach gpiorestart_ca = {
+ sizeof(struct gpiorestart_softc), gpiorestart_match, gpiorestart_attach
+};
+
+struct cfdriver gpiorestart_cd = {
+ NULL, "gpiorestart", DV_DULL
+};
+
+void gpiorestart_reset(void);
+
+int
+gpiorestart_match(struct device *parent, void *match, void *aux)
+{
+ struct fdt_attach_args *faa = aux;
+
+ return OF_is_compatible(faa->fa_node, "gpio-restart");
+}
+
+void
+gpiorestart_attach(struct device *parent, struct device *self, void *aux)
+{
+ struct gpiorestart_softc *sc = (struct gpiorestart_softc *)self;
+ struct fdt_attach_args *faa = aux;
+ int len;
+
+ len = OF_getproplen(faa->fa_node, "gpios");
+ if (len <= 0) {
+ printf(": no gpio\n");
+ return;
+ }
+
+ sc->sc_gpio = malloc(len, M_DEVBUF, M_WAITOK);
+ OF_getpropintarray(faa->fa_node, "gpios", sc->sc_gpio, len);
+
+ sc->sc_active_delay =
+ OF_getpropint(faa->fa_node, "active-delay", 100) * 1000;
+ sc->sc_inactive_delay =
+ OF_getpropint(faa->fa_node, "inactive-delay", 100) * 1000;
+ sc->sc_wait_delay =
+ OF_getpropint(faa->fa_node, "wait-delay", 3000) * 1000;
+
+ if (cpuresetfn == NULL)
+ cpuresetfn = gpiorestart_reset;
+
+ printf("\n");
+}
+
+void
+gpiorestart_reset(void)
+{
+ struct gpiorestart_softc *sc = gpiorestart_cd.cd_devs[0];
+
+ gpio_controller_config_pin(sc->sc_gpio, GPIO_CONFIG_OUTPUT);
+ gpio_controller_set_pin(sc->sc_gpio, 1);
+ delay(sc->sc_active_delay);
+ gpio_controller_set_pin(sc->sc_gpio, 0);
+ delay(sc->sc_inactive_delay);
+ gpio_controller_set_pin(sc->sc_gpio, 1);
+ delay(sc->sc_wait_delay);
+}