iWe must be careful to only disable power domains that are no longer in

use by a device.  So maintainer a counter and only disable the power
domain if it drops to zero.

ok deraadt@, tobhe@

diff --git a/sys/arch/arm64/dev/aplpmgr.c b/sys/arch/arm64/dev/aplpmgr.c
index 6b8d46c..2525a44 100644 (file)
--- a/sys/arch/arm64/dev/aplpmgr.c
+++ b/sys/arch/arm64/dev/aplpmgr.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: aplpmgr.c,v 1.2 2022/11/09 16:23:51 kettenis Exp $    */
+/*     $OpenBSD: aplpmgr.c,v 1.3 2022/11/10 11:44:06 kettenis Exp $    */
 /*
  * Copyright (c) 2021 Mark Kettenis <kettenis@openbsd.org>
  *
@@ -50,6 +50,7 @@ struct aplpmgr_softc;
 struct aplpmgr_pwrstate {
        struct aplpmgr_softc    *ps_sc;
        bus_size_t              ps_offset;
+       int                     ps_enablecount;
        struct power_domain_device ps_pd;
        struct reset_device     ps_rd;
 };
@@ -65,6 +66,7 @@ struct aplpmgr_softc {
 
 int    aplpmgr_match(struct device *, void *, void *);
 void   aplpmgr_attach(struct device *, struct device *, void *);
+int    aplpmgr_activate(struct device *, int act);
 
 const struct cfattach aplpmgr_ca = {
        sizeof (struct aplpmgr_softc), aplpmgr_match, aplpmgr_attach
@@ -133,6 +135,8 @@ aplpmgr_attach(struct device *parent, struct device *self, void *aux)
 
                ps->ps_sc = sc;
                ps->ps_offset = reg[0];
+               if (OF_getpropbool(node, "apple,always-on"))
+                       ps->ps_enablecount = 1;
 
                ps->ps_pd.pd_node = node;
                ps->ps_pd.pd_cookie = ps;
@@ -157,7 +161,25 @@ aplpmgr_enable(void *cookie, uint32_t *cells, int on)
        uint32_t val;
        int timo;
 
-       power_domain_enable_all(ps->ps_pd.pd_node);
+       KASSERT(on || ps->ps_enablecount > 0);
+       KASSERT(!on || ps->ps_enablecount < INT_MAX);
+
+       if (on && ps->ps_enablecount > 0) {
+               power_domain_enable_all(ps->ps_pd.pd_node);
+               ps->ps_enablecount++;
+               return;
+       }
+       if (!on && ps->ps_enablecount > 1) {
+               power_domain_disable_all(ps->ps_pd.pd_node);
+               ps->ps_enablecount--;
+               return;
+       }
+
+       /* Enable parents before enabling ourselves. */
+       if (on) {
+               power_domain_enable_all(ps->ps_pd.pd_node);
+               ps->ps_enablecount++;
+       }
 
        val = HREAD4(sc, ps->ps_offset);
        val &= ~PMGR_PS_TARGET_MASK;
@@ -171,6 +193,12 @@ aplpmgr_enable(void *cookie, uint32_t *cells, int on)
                        break;
                delay(1);
        }
+
+       /* Disable parents after disabling ourselves. */
+       if (!on) {
+               power_domain_disable_all(ps->ps_pd.pd_node);
+               ps->ps_enablecount--;
+       }
 }
 
 void