diff --git a/build/soong/selinux.go b/build/soong/selinux.go
index f811231..51ff732 100644
--- a/build/soong/selinux.go
+++ b/build/soong/selinux.go
@@ -16,6 +16,7 @@
 
 import (
 	"github.com/google/blueprint"
+	"github.com/google/blueprint/proptools"
 
 	"android/soong/android"
 )
@@ -50,3 +51,12 @@
 	}
 	return flagMacros
 }
+
+// boardApiLevel returns the M4 argument containing the target board API level.
+func boardApiLevelToM4Macro(ctx android.ModuleContext, apiLevel *string) string {
+	level := proptools.StringDefault(apiLevel, "current")
+	if level == "current" {
+		level = ctx.Config().VendorApiLevel()
+	}
+	return "-D target_board_api_level=" + level
+}