From a89516b31c8c0a41b4955fbcee764901232d71b1 Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Tue, 16 Apr 2013 08:43:58 +0530 Subject: [PATCH] ARC: [kbuild] Avoid DTB rebuilds if DTS are untouched Currently, for every ARC kernel build I see the following: --------------->8----------------- DTB arch/arc/boot/dts/angel4.dtb.S AS arch/arc/boot/dts/angel4.dtb.o LD arch/arc/boot/dts/built-in.o rm arch/arc/boot/dts/angel4.dtb.S <-- forces rebuild next iter CHK kernel/config_data.h --------------->8----------------- This is because *.dts.S is intermediate file in dtb generation and is by default deleted by make which needs a ".SECONDARY" hint to NOT do so. This could have ideally been done in scripts/Makefile.lib - for benefit of all, however .SECONDARY doesn't seem to work with wildcards. Thanks to Stephen for suggesting .SECONDARY (vs .PRECIOUS) and making that work using a non wildcard version in arch makefile. Thanks to James Hogan for pointing out that *.dtb.S now needs to be added to clean-files Signed-off-by: Stephen Warren Signed-off-by: Vineet Gupta --- arch/arc/boot/dts/Makefile | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/arc/boot/dts/Makefile b/arch/arc/boot/dts/Makefile index 5776835d583f..faf240e29ec2 100644 --- a/arch/arc/boot/dts/Makefile +++ b/arch/arc/boot/dts/Makefile @@ -8,6 +8,8 @@ endif obj-y += $(builtindtb-y).dtb.o targets += $(builtindtb-y).dtb +.SECONDARY: $(obj)/$(builtindtb-y).dtb.S + dtbs: $(addprefix $(obj)/, $(builtindtb-y).dtb) -clean-files := *.dtb +clean-files := *.dtb *.dtb.S -- 2.20.1