diff --git a/arch/arm64/tools/gen-sysreg.awk b/arch/arm64/tools/gen-sysreg.awk
index 86860ab672dc..53844f5c5e52 100755
--- a/arch/arm64/tools/gen-sysreg.awk
+++ b/arch/arm64/tools/gen-sysreg.awk
@@ -228,7 +228,7 @@ $1 == "EndSysreg" && block_current() == "Sysreg" {
 }
 
 # Currently this is effectivey a comment, in future we may want to emit
-# defines for the fields.
+# defines for the fields. We do emit RESx and UNKN values in any case.
 ($1 == "Fields" || $1 == "Mapping") && block_current() == "Sysreg" {
 	expect_fields(2)
 
@@ -239,9 +239,9 @@ $1 == "EndSysreg" && block_current() == "Sysreg" {
 	print ""
 
 	next_bit = -1
-	res0 = null
-	res1 = null
-	unkn = null
+	res0 = $2 "_RES0"
+	res1 = $2 "_RES1"
+	unkn = $2 "_UNKN"
 
 	next
 }