Hack to enable automatic reboot after a power failure for NetBSD/macppc machines with pmu(4). Based on FreeBSD's.

pmu.diff

--- pmu.c.orig	2019-06-26 19:18:48.350013535 -0700
+++ pmu.c	2019-06-26 19:30:25.636761664 -0700
@@ -148,16 +148,17 @@
 /* i2c stuff */
 #if 0
 static int pmu_i2c_acquire_bus(void *, int);
 static void pmu_i2c_release_bus(void *, int);
 static int pmu_i2c_exec(void *, i2c_op_t, i2c_addr_t, const void *, size_t,
 		    void *, size_t, int);
 #endif
 
+static void pmu_server_mode(struct pmu_softc *);
 static void pmu_attach_legacy_battery(struct pmu_softc *);
 static void pmu_attach_smart_battery(struct pmu_softc *, int);
 static int  pmu_print(void *, const char *);
 
 /* these values shows that number of data returned after 'send' cmd is sent */
 static signed char pm_send_cmd_type[] = {
 	  -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,
 	  -1,   -1,   -1,   -1,   -1,   -1,   -1,   -1,
@@ -406,16 +407,19 @@
 		if (OF_getprop(pmnode, "prim-info", regs, sizeof(regs)) < 24)
 			goto bat_done;
 		nbat = regs[6] >> 16;
 		for (i = 0; i < nbat; i++)
 			pmu_attach_smart_battery(sc, i);
 	}
 bat_done:
 
+	/* try to enable power fail mode */
+	pmu_server_mode(sc);
+
 #if notyet
 	memset(&iba, 0, sizeof(iba));
 	iba.iba_tag = &sc->sc_i2c;
 	sc->sc_i2c.ic_cookie = sc;
 	sc->sc_i2c.ic_acquire_bus = pmu_i2c_acquire_bus;
 	sc->sc_i2c.ic_release_bus = pmu_i2c_release_bus;
 	sc->sc_i2c.ic_send_start = NULL;
 	sc->sc_i2c.ic_send_stop = NULL;
@@ -1081,16 +1085,38 @@
 static int
 pmu_print(void *aux, const char *what)
 {
 
 	return 0;
 }
 
 static void
+pmu_server_mode(struct pmu_softc *sc)
+{
+	uint8_t getcmd[] = {PMU_PWR_GET_POWERUP_EVENTS};
+	uint8_t setcmd[3];
+	uint8_t resp[3];
+	int len;
+
+	len = pmu_send(sc, PMU_POWER_EVENTS, 1, getcmd, 3, resp);
+	if (len != 3) {
+		DPRINTF("pmu_server_mode query abnormal return length: %d\n",
+			len);
+		return;
+	}
+
+	setcmd[0] = PMU_PWR_SET_POWERUP_EVENTS;
+	setcmd[1] = resp[1];
+	setcmd[2] = PMU_PWR_WAKEUP_AC_INSERT;
+
+	(void)pmu_send(sc, PMU_POWER_EVENTS, 3, setcmd, 2, resp);
+}
+
+static void
 pmu_attach_legacy_battery(struct pmu_softc *sc)
 {
 	struct battery_attach_args baa;
 
 	baa.baa_type = BATTERY_TYPE_LEGACY;
 	baa.baa_pmu_ops = &sc->sc_pmu_ops;
 	config_found_ia(sc->sc_dev, "pmu_bus", &baa, pmu_print);
 }