diff --git a/sys/dev/acpica/acpi.c b/sys/dev/acpica/acpi.c
index 9fe823a0825c..6679ebf4070c 100644
--- a/sys/dev/acpica/acpi.c
+++ b/sys/dev/acpica/acpi.c
@@ -900,9 +900,6 @@ acpi_read_ivar(device_t dev, device_t child, int index, uintptr_t *result)
     case ACPI_IVAR_HANDLE:
 	*(ACPI_HANDLE *)result = ad->ad_handle;
 	break;
-    case ACPI_IVAR_MAGIC:
-	*(uintptr_t *)result = ad->ad_magic;
-	break;
     case ACPI_IVAR_PRIVATE:
 	*(void **)result = ad->ad_private;
 	break;
@@ -938,9 +935,6 @@ acpi_write_ivar(device_t dev, device_t child, int index, uintptr_t value)
     case ACPI_IVAR_HANDLE:
 	ad->ad_handle = (ACPI_HANDLE)value;
 	break;
-    case ACPI_IVAR_MAGIC:
-	ad->ad_magic = (uintptr_t)value;
-	break;
     case ACPI_IVAR_PRIVATE:
 	ad->ad_private = (void *)value;
 	break;
diff --git a/sys/dev/acpica/acpi_cpu.c b/sys/dev/acpica/acpi_cpu.c
index 8fe9de6f61ce..c16dcb17416a 100644
--- a/sys/dev/acpica/acpi_cpu.c
+++ b/sys/dev/acpica/acpi_cpu.c
@@ -255,7 +255,7 @@ acpi_cpu_probe(device_t dev)
 
     /* Mark this processor as in-use and save our derived id for attach. */
     cpu_softc[cpu_id] = (void *)1;
-    acpi_set_magic(dev, cpu_id);
+    acpi_set_private(dev, (void*)(intptr_t)cpu_id);
     device_set_desc(dev, "ACPI CPU");
 
     return (0);
@@ -286,7 +286,7 @@ acpi_cpu_attach(device_t dev)
     sc = device_get_softc(dev);
     sc->cpu_dev = dev;
     sc->cpu_handle = acpi_get_handle(dev);
-    cpu_id = acpi_get_magic(dev);
+    cpu_id = (int)(intptr_t)acpi_get_private(dev);
     cpu_softc[cpu_id] = sc;
     pcpu_data = pcpu_find(cpu_id);
     pcpu_data->pc_device = dev;
diff --git a/sys/dev/acpica/acpi_ec.c b/sys/dev/acpica/acpi_ec.c
index a5a81dc632f4..b339ba10ed0d 100644
--- a/sys/dev/acpica/acpi_ec.c
+++ b/sys/dev/acpica/acpi_ec.c
@@ -129,9 +129,6 @@ struct acpi_ec_params {
     int		uid;
 };
 
-/* Indicate that this device has already been probed via ECDT. */
-#define DEV_ECDT(x)	(acpi_get_magic(x) == (uintptr_t)&acpi_ec_devclass)
-
 /*
  * Driver softc.
  */
@@ -332,7 +329,6 @@ acpi_ec_ecdt_probe(device_t parent)
     params->uid = ecdt->Uid;
     acpi_GetInteger(h, "_GLK", &params->glk);
     acpi_set_private(child, params);
-    acpi_set_magic(child, (uintptr_t)&acpi_ec_devclass);
 
     /* Finish the attach process. */
     if (device_probe_and_attach(child) != 0)
@@ -348,6 +344,7 @@ acpi_ec_probe(device_t dev)
     ACPI_STATUS status;
     device_t	peer;
     char	desc[64];
+    int		ecdt;
     int		ret;
     struct acpi_ec_params *params;
     static char *ec_ids[] = { "PNP0C09", NULL };
@@ -362,11 +359,12 @@ acpi_ec_probe(device_t dev)
      * duplicate probe.
      */
     ret = ENXIO;
-    params = NULL;
+    ecdt = 0;
     buf.Pointer = NULL;
     buf.Length = ACPI_ALLOCATE_BUFFER;
-    if (DEV_ECDT(dev)) {
-	params = acpi_get_private(dev);
+    params = acpi_get_private(dev);
+    if (params != NULL) {
+	ecdt = 1;
 	ret = 0;
     } else if (!acpi_disabled("ec") &&
 	ACPI_ID_PROBE(device_get_parent(dev), dev, ec_ids)) {
@@ -439,7 +437,7 @@ acpi_ec_probe(device_t dev)
     if (ret == 0) {
 	snprintf(desc, sizeof(desc), "Embedded Controller: GPE %#x%s%s",
 		 params->gpe_bit, (params->glk) ? ", GLK" : "",
-		 DEV_ECDT(dev) ? ", ECDT" : "");
+		 ecdt ? ", ECDT" : "");
 	device_set_desc_copy(dev, desc);
     }
 
diff --git a/sys/dev/acpica/acpi_hpet.c b/sys/dev/acpica/acpi_hpet.c
index a41869543680..ee346b7ddff3 100644
--- a/sys/dev/acpica/acpi_hpet.c
+++ b/sys/dev/acpica/acpi_hpet.c
@@ -61,8 +61,6 @@ static void acpi_hpet_test(struct acpi_hpet_softc *sc);
 
 static char *hpet_ids[] = { "PNP0103", NULL };
 
-#define DEV_HPET(x)	(acpi_get_magic(x) == (uintptr_t)&acpi_hpet_devclass)
-
 struct timecounter hpet_timecounter = {
 	.tc_get_timecount =	hpet_get_timecount,
 	.tc_counter_mask =	~0u,
@@ -133,8 +131,6 @@ acpi_hpet_identify(driver_t *driver, device_t parent)
 		return;
 	}
 
-	/* Record a magic value so we can detect this device later. */
-	acpi_set_magic(child, (uintptr_t)&acpi_hpet_devclass);
 	bus_set_resource(child, SYS_RES_MEMORY, 0, hpet->Address.Address,
 	    HPET_MEM_WIDTH);
 }
@@ -146,7 +142,7 @@ acpi_hpet_probe(device_t dev)
 
 	if (acpi_disabled("hpet"))
 		return (ENXIO);
-	if (!DEV_HPET(dev) &&
+	if (acpi_get_handle(dev) != NULL &&
 	    (ACPI_ID_PROBE(device_get_parent(dev), dev, hpet_ids) == NULL ||
 	    device_get_unit(dev) != 0))
 		return (ENXIO);
diff --git a/sys/dev/acpica/acpivar.h b/sys/dev/acpica/acpivar.h
index f4d27e4738cf..abfaa8b1f2b2 100644
--- a/sys/dev/acpica/acpivar.h
+++ b/sys/dev/acpica/acpivar.h
@@ -88,7 +88,6 @@ struct acpi_softc {
 struct acpi_device {
     /* ACPI ivars */
     ACPI_HANDLE			ad_handle;
-    uintptr_t			ad_magic;
     void			*ad_private;
     int				ad_flags;
 
@@ -224,7 +223,7 @@ extern int	acpi_quirks;
  * attach to ACPI.
  */
 #define ACPI_IVAR_HANDLE	0x100
-#define ACPI_IVAR_MAGIC		0x101
+#define ACPI_IVAR_UNUSED	0x101	/* Unused/reserved. */
 #define ACPI_IVAR_PRIVATE	0x102
 #define ACPI_IVAR_FLAGS		0x103
 
@@ -250,7 +249,6 @@ static __inline void varp ## _set_ ## var(device_t dev, type t)	\
 }
 
 __ACPI_BUS_ACCESSOR(acpi, handle, ACPI, HANDLE, ACPI_HANDLE)
-__ACPI_BUS_ACCESSOR(acpi, magic, ACPI, MAGIC, uintptr_t)
 __ACPI_BUS_ACCESSOR(acpi, private, ACPI, PRIVATE, void *)
 __ACPI_BUS_ACCESSOR(acpi, flags, ACPI, FLAGS, int)