Add BR2_EXTERNAL skeleton

board/raspberrypi/post_image.sh

@@ -0,0 +1,35 @@
+#!/bin/sh
+# post_image.sh - Common post-image script for Raspberry Pi
+#
+# Called by Buildroot after filesystem images (ext4, etc.) are generated.
+# Arguments:
+#   $1 = path to the images directory (e.g., output/images)
+#
+# Environment:
+#   BR2_EXTERNAL_RPI_COMMON_PATH = path to this external tree
+#   BINARIES_DIR                 = same as $1
+#   BUILD_DIR                    = path to the build directory
+#
+# This script uses genimage to assemble the final SD card image
+# from the boot files and root filesystem.
+
+set -e
+
+BOARD_DIR="${BR2_EXTERNAL_RPI_COMMON_PATH}/board/raspberrypi"
+
+# Use project-specific genimage.cfg if it exists, otherwise use common one.
+# Projects can override by setting GENIMAGE_CFG in their own post-image script.
+GENIMAGE_CFG="${GENIMAGE_CFG:-${BOARD_DIR}/genimage.cfg}"
+
+# genimage requires a temporary directory
+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}"
+
+echo ">>> SD card image generated: ${BINARIES_DIR}/sdcard.img"