Index: sys/dev/acpica/acpi.c =================================================================== --- sys/dev/acpica/acpi.c +++ sys/dev/acpica/acpi.c @@ -2260,6 +2260,15 @@ /* Never disable PCI link devices. */ if (acpi_MatchHid(handle, "PNP0C0F")) break; + + /* + * RTC Device should be enabled for CMOS register space + * unless FADT indicate it is not present. + * (checked in RTC probe routine.) + */ + if (acpi_MatchHid(handle, "PNP0B00")) + break; + /* * Docking stations should remain enabled since the system * may be undocked at boot. 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))) {