Index: sys/x86/isa/atrtc.c
===================================================================
--- sys/x86/isa/atrtc.c
+++ sys/x86/isa/atrtc.c
@@ -370,7 +370,10 @@
 	if (acpi_disabled("atrtc"))
 		return (ENXIO);
 
-	sc->acpi_handle = acpi_get_handle(dev);
+	if(ACPI_FAILURE(AcpiGetHandle(ACPI_ROOT_OBJECT, "\\_SB_", &sc->acpi_handle))){
+		return (ENXIO);
+	}
+
 	if (sc->acpi_handle == NULL ||
 	    ACPI_FAILURE(AcpiInstallAddressSpaceHandler(sc->acpi_handle,
 	      ACPI_ADR_SPACE_CMOS, atrtc_acpi_cmos_handler, NULL, dev))) {