[Buildroot] [PATCH 5/5] grub2: introduce BR2_TARGET_GRUB2_CFG

[Erico Nunes]

This configuration can be used to provide a custom Grub 2 configuration
file containing menu entries. In the previous implementation, this had
to be always done by an external script, overwriting the defualt image.
This should be backwards compatible as the default value is the previous
hardcoded value.

Signed-off-by: Erico Nunes <nunes.erico at gmail.com>
---
 boot/grub2/Config.in | 7 +++++++
 boot/grub2/grub2.mk  | 5 +++--
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/boot/grub2/Config.in b/boot/grub2/Config.in
index 527ff37..94862a6 100644
--- a/boot/grub2/Config.in
+++ b/boot/grub2/Config.in
@@ -196,4 +196,11 @@ config BR2_TARGET_GRUB2_BUILTIN_CONFIG
 	  device and other configuration parameters, but however menu
 	  entries cannot be described in this embedded configuration.
 
+config BR2_TARGET_GRUB2_CFG
+	string "grub2 menu entries config"
+	default "boot/grub2/grub.cfg"
+	help
+	  Path to a Grub 2 configuration file containing the grub2 menu
+	  entries.
+
 endif # BR2_TARGET_GRUB2
diff --git a/boot/grub2/grub2.mk b/boot/grub2/grub2.mk
index 910967e..7a64b60 100644
--- a/boot/grub2/grub2.mk
+++ b/boot/grub2/grub2.mk
@@ -110,8 +110,9 @@ define GRUB2_INSTALL_IMAGES_CMDS
 		-p "$(GRUB2_PREFIX)" \
 		$(if $(GRUB2_BUILTIN_CONFIG),-c $(GRUB2_BUILTIN_CONFIG)) \
 		$(GRUB2_BUILTIN_MODULES)
-	mkdir -p $(dir $(GRUB2_CFG))
-	$(INSTALL) -D -m 0644 boot/grub2/grub.cfg $(GRUB2_CFG)
+	$(if $(BR2_TARGET_GRUB2_CFG), \
+		mkdir -p $(dir $(GRUB2_CFG)) && \
+		$(INSTALL) -D -m 0644 $(BR2_TARGET_GRUB2_CFG) $(GRUB2_CFG))
 	$(GRUB2_IMAGE_INSTALL_ELTORITO)
 endef
 
-- 
2.9.3