diff --git a/sys/i386/acpica/acpi_machdep.c b/sys/i386/acpica/acpi_machdep.c
index b6517ba53e1d..9c59b3a5b06c 100644
--- a/sys/i386/acpica/acpi_machdep.c
+++ b/sys/i386/acpica/acpi_machdep.c
@@ -328,7 +328,10 @@ acpi_machdep_init(device_t dev)
 
 	acpi_install_wakeup_handler(sc);
 
-	if (intr_model != ACPI_INTR_PIC)
+	if (intr_model == ACPI_INTR_PIC)
+		BUS_CONFIG_INTR(dev, AcpiGbl_FADT->SciInt, INTR_TRIGGER_LEVEL,
+		    INTR_POLARITY_LOW);
+	else
 		acpi_SetIntrModel(intr_model);
 
 	SYSCTL_ADD_UINT(&sc->acpi_sysctl_ctx,