include scripts/Kbuild.include
+# If arch does not implement mandatory headers, fallback to asm-generic ones.
+mandatory-y := $(filter-out $(generated-y), $(mandatory-y))
+generic-y += $(foreach f, $(mandatory-y), $(if $(wildcard $(srctree)/$(src)/$(f)),,$(f)))
+
generic-y := $(addprefix $(obj)/, $(generic-y))
generated-y := $(addprefix $(obj)/, $(generated-y))