kbuild: Consolidate header generation from ASM offset information

Largely redundant code is used in different places to generate C headers
from offset information extracted from assembly language output.
Consolidate the code in Makefile.lib and use this instead.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

2 files changed, 30 insertions, 26 deletions

diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 0a07f9014944..dd567e5d59e0 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -408,3 +408,31 @@ quiet_cmd_xzmisc = XZMISC  $@
 cmd_xzmisc = (cat $(filter-out FORCE,$^) | \
         xz --check=crc32 --lzma2=dict=1MiB) > $@ || \
         (rm -f $@ ; false)
+
+# ASM offsets
+# ---------------------------------------------------------------------------
+
+# Default sed regexp - multiline due to syntax constraints
+define sed-offsets
+        "/^->/{s:->#\(.*\):/* \1 */:; \
+        s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 \2 /* \3 */:; \
+        s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
+        s:->::; p;}"
+endef
+
+# Use filechk to avoid rebuilds when a header changes, but the resulting file
+# does not
+define filechk_offsets
+        (set -e; \
+         echo "#ifndef $2"; \
+         echo "#define $2"; \
+         echo "/*"; \
+         echo " * DO NOT MODIFY."; \
+         echo " *"; \
+         echo " * This file was generated by Kbuild"; \
+         echo " */"; \
+         echo ""; \
+         sed -ne $(sed-offsets); \
+         echo ""; \
+         echo "#endif" )
+endef
diff --git a/scripts/mod/Makefile b/scripts/mod/Makefile
index 19d9bcadc0cc..b497d9764dcf 100644
--- a/scripts/mod/Makefile
+++ b/scripts/mod/Makefile
@@ -7,32 +7,8 @@ modpost-objs	:= modpost.o file2alias.o sumversion.o
 
 devicetable-offsets-file := devicetable-offsets.h
 
-define sed-y
-        "/^->/{s:->#\(.*\):/* \1 */:; \
-        s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 \2 /* \3 */:; \
-        s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
-        s:->::; p;}"
-endef
-
-quiet_cmd_offsets = GEN     $@
-define cmd_offsets
-        (set -e; \
-         echo "#ifndef __DEVICETABLE_OFFSETS_H__"; \
-         echo "#define __DEVICETABLE_OFFSETS_H__"; \
-         echo "/*"; \
-         echo " * DO NOT MODIFY."; \
-         echo " *"; \
-         echo " * This file was generated by Kbuild"; \
-         echo " *"; \
-         echo " */"; \
-         echo ""; \
-         sed -ne $(sed-y) $<; \
-         echo ""; \
-         echo "#endif" ) > $@
-endef
-
-$(obj)/$(devicetable-offsets-file): $(obj)/devicetable-offsets.s
-        $(call if_changed,offsets)
+$(obj)/$(devicetable-offsets-file): $(obj)/devicetable-offsets.s FORCE
+        $(call filechk,offsets,__DEVICETABLE_OFFSETS_H__)
 
 targets += $(devicetable-offsets-file) devicetable-offsets.s