[Buildroot] [PATCH v2 1/3] configs/pc: refactor to use genimage and grub.cfg

[Erico Nunes <nunes.erico@gmail.com>]

This simplifies the pc configs and respective post image scripts to use
the shared genimage script and separate grub config files.
Separate grub files are cleaner to maintain and easier to copy and
modify, for example to support booting the pc defconfigs in qemu.

Signed-off-by: Erico Nunes <nunes.erico@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
---
Changes v1 -> v2:
  - Drop the BR2_TARGET_GRUB2_CFG proposed use since the patch was
  dropped.
---
 board/pc/grub-bios.cfg           |  6 ++++++
 board/pc/grub-efi.cfg            |  6 ++++++
 board/pc/post-image.sh           | 29 ++++-------------------------
 configs/pc_x86_64_bios_defconfig |  3 ++-
 configs/pc_x86_64_efi_defconfig  |  3 ++-
 5 files changed, 20 insertions(+), 27 deletions(-)
 create mode 100644 board/pc/grub-bios.cfg
 create mode 100755 board/pc/grub-efi.cfg

diff --git a/board/pc/grub-bios.cfg b/board/pc/grub-bios.cfg
new file mode 100644
index 0000000000..bd3e3f0006
--- /dev/null
+++ b/board/pc/grub-bios.cfg
@@ -0,0 +1,6 @@
+set default="0"
+set timeout="5"
+
+menuentry "Buildroot" {
+	linux /boot/bzImage root=/dev/sda1 rootwait console=tty1
+}
diff --git a/board/pc/grub-efi.cfg b/board/pc/grub-efi.cfg
new file mode 100755
index 0000000000..222301a4e0
--- /dev/null
+++ b/board/pc/grub-efi.cfg
@@ -0,0 +1,6 @@
+set default="0"
+set timeout="5"
+
+menuentry "Buildroot" {
+	linux /bzImage root=/dev/sda2 rootwait console=tty1
+}
diff --git a/board/pc/post-image.sh b/board/pc/post-image.sh
index c88ecb1dc2..bdd0847ec5 100755
--- a/board/pc/post-image.sh
+++ b/board/pc/post-image.sh
@@ -1,35 +1,14 @@
 #!/bin/sh
 
+BOARD_DIR="$(dirname $0)"
+
 # Detect boot strategy, EFI or BIOS
 if [ -f ${BINARIES_DIR}/efi-part/startup.nsh ]; then
-  BOOT_TYPE=efi
-  # grub.cfg needs customization for EFI since the root partition is
-  # number 2, and bzImage is in the EFI partition (1)
-  cat >${BINARIES_DIR}/efi-part/EFI/BOOT/grub.cfg <<__EOF__
-set default="0"
-set timeout="5"
-
-menuentry "Buildroot" {
-	linux /bzImage root=/dev/sda2 rootwait console=tty1
-}
-__EOF__
+  cp -f ${BOARD_DIR}/grub-efi.cfg ${BINARIES_DIR}/efi-part/EFI/BOOT/grub.cfg
 else
-  BOOT_TYPE=bios
+  cp -f ${BOARD_DIR}/grub-bios.cfg ${TARGET_DIR}/boot/grub/grub.cfg
   # Copy grub 1st stage to binaries, required for genimage
   cp -f ${HOST_DIR}/lib/grub/i386-pc/boot.img ${BINARIES_DIR}
 fi
 
-BOARD_DIR="$(dirname $0)"
-GENIMAGE_CFG="${BOARD_DIR}/genimage-${BOOT_TYPE}.cfg"
-GENIMAGE_TMP="${BUILD_DIR}/genimage.tmp"
-
-rm -rf "${GENIMAGE_TMP}"
-
-genimage                           \
-       --rootpath "${TARGET_DIR}"     \
-       --tmppath "${GENIMAGE_TMP}"    \
-       --inputpath "${BINARIES_DIR}"  \
-       --outputpath "${BINARIES_DIR}" \
-       --config "${GENIMAGE_CFG}"
-
 exit $?
diff --git a/configs/pc_x86_64_bios_defconfig b/configs/pc_x86_64_bios_defconfig
index ddbd776154..47787bc118 100644
--- a/configs/pc_x86_64_bios_defconfig
+++ b/configs/pc_x86_64_bios_defconfig
@@ -19,7 +19,8 @@ BR2_TARGET_ROOTFS_EXT2=y
 BR2_TARGET_ROOTFS_EXT2_4=y
 BR2_TARGET_ROOTFS_EXT2_SIZE="120M"
 # BR2_TARGET_ROOTFS_TAR is not set
-BR2_ROOTFS_POST_IMAGE_SCRIPT="board/pc/post-image.sh"
+BR2_ROOTFS_POST_IMAGE_SCRIPT="board/pc/post-image.sh support/scripts/genimage.sh"
+BR2_ROOTFS_POST_SCRIPT_ARGS="-c board/pc/genimage-bios.cfg"
 
 # Linux headers same as kernel, a 4.13 series
 BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_4_13=y
diff --git a/configs/pc_x86_64_efi_defconfig b/configs/pc_x86_64_efi_defconfig
index 94385252b9..67ba5bcf5b 100644
--- a/configs/pc_x86_64_efi_defconfig
+++ b/configs/pc_x86_64_efi_defconfig
@@ -22,7 +22,8 @@ BR2_TARGET_ROOTFS_EXT2=y
 BR2_TARGET_ROOTFS_EXT2_4=y
 BR2_TARGET_ROOTFS_EXT2_SIZE="120M"
 # BR2_TARGET_ROOTFS_TAR is not set
-BR2_ROOTFS_POST_IMAGE_SCRIPT="board/pc/post-image.sh"
+BR2_ROOTFS_POST_IMAGE_SCRIPT="board/pc/post-image.sh support/scripts/genimage.sh"
+BR2_ROOTFS_POST_SCRIPT_ARGS="-c board/pc/genimage-efi.cfg"
 
 # Linux headers same as kernel, a 4.13 series
 BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_4_13=y
-- 
2.13.6