Change in coreboot[master]: payloads/external/GRUB2: Only rebuild on config changes

[Nico Huber (Code Review)]

Nico Huber has uploaded this change for review. ( https://review.coreboot.org/20991

Change subject: payloads/external/GRUB2: Only rebuild on config changes
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payloads/external/GRUB2: Only rebuild on config changes

Change-Id: I376eea9a3e02b03010fc5c5a05199ea7b2813220
Signed-off-by: Nico Huber 
---
M payloads/external/GRUB2/Makefile
M payloads/external/Makefile.inc
2 files changed, 5 insertions(+), 2 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/91/20991/1

diff --git a/payloads/external/GRUB2/Makefile b/payloads/external/GRUB2/Makefile
index dee7f69..4a0a491 100644
--- a/payloads/external/GRUB2/Makefile
+++ b/payloads/external/GRUB2/Makefile
@@ -22,7 +22,7 @@
    		git branch -f $(NAME-y) $(TAG-y) && \
    		git checkout $(NAME-y) || true

-config: checkout
+grub2/build/config.h: $(CONFIG_DEP) | checkout
    echo "    CONFIG     GRUB2 $(NAME-y)"
    rm -rf grub2/build
    mkdir grub2/build
@@ -32,6 +32,8 @@
    CFLAGS=-O2 TARGET_CFLAGS=-Os \
    --with-platform=coreboot --enable-boot-time --disable-werror

+config: grub2/build/config.h checkout
+
 grub2: config
    echo "    MAKE       GRUB2 $(NAME-y)"
    $(MAKE) -C grub2/build
diff --git a/payloads/external/Makefile.inc b/payloads/external/Makefile.inc
index fb50604..0a9b3d6 100644
--- a/payloads/external/Makefile.inc
+++ b/payloads/external/Makefile.inc
@@ -152,11 +152,12 @@

# Grub

-grub2:
+grub2: $(obj)/config.h
    $(MAKE) -C payloads/external/GRUB2 \
    		HOSTCC="$(HOSTCC)" \
    		CC="$(CC_x86_32)" LD="$(LD_x86_32)" \
    		OBJCOPY="$(OBJCOPY_x86_32)" STRIP="$(STRIP_x86_32)" \
+			CONFIG_DEP="$(abspath $(obj)/config.h)" \
    		CONFIG_GRUB2_MASTER=$(CONFIG_GRUB2_MASTER) \
    		CONFIG_GRUB2_REVISION=$(CONFIG_GRUB2_REVISION) \
    		CONFIG_GRUB2_REVISION_ID=$(CONFIG_GRUB2_REVISION_ID) \