board/freescale: factorize genimage logic

For the boards imx6ulevk, imx6sabresd, mx25pdk, mx51evk, mx53loco,
warpboard:
* Replace genimage.cfg with a common Freescale genimage template named
  genimage.cfg.template because they all use the same layout.  The only
  difference comes from the device tree blobs.
* Replace each post-image.sh script with a generic post-image.sh script
  which is able to generate the right genimage.cfg depending on:
** the image type (zImage or uImage) from BR2_LINUX_KERNEL_UIMAGE
** the device tree blobs from BR2_LINUX_KERNEL_INTREE_DTS_NAME
** the rootfs type (ext2, ext3 or ext4) from BR2_TARGET_ROOTFS_EXT2
* Fix the readme.txt files accordingly

Signed-off-by: Georges Savoundararadj <savoundg@gmail.com>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Peter Korsgaard <peter@korsgaard.com>
Cc: Yann E. MORIN <yann.morin.1998@free.fr>
[Thomas: remove handling of rootfs type, using rootfs.ext2 in all cases
is fine, rootfs.ext3 and rootfs.ext4 are just symbolic links to it.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

board/freescale/common/genimage.cfg.template

@@ -0,0 +1,40 @@
+# Minimal SD card image for the Freescale boards Template
+#
+# We mimic the .sdcard Freescale's image format:
+# * the SD card must have 1 kB free space at the beginning,
+# * U-Boot is dumped as is,
+# * a FAT partition at offset 8 MB is containing zImage/uImage and DTB files
+# * a single root filesystem partition is required (ext2, ext3 or ext4)
+#
+
+image boot.vfat {
+  vfat {
+    files = {
+      %FILES%
+    }
+  }
+  size = 16M
+}
+
+image sdcard.img {
+  hdimage {
+  }
+
+  partition u-boot {
+    in-partition-table = "no"
+    image = "u-boot.imx"
+    offset = 1024
+  }
+
+  partition boot {
+    partition-type = 0xC
+    bootable = "true"
+    image = "boot.vfat"
+    offset = 8M
+  }
+
+  partition rootfs {
+    partition-type = 0x83
+    image = "rootfs.ext2"
+  }
+}

board/freescale/common/post-image.sh

@@ -0,0 +1,54 @@
+#!/usr/bin/env bash
+
+#
+# dtb_list extracts the list of DTB files from BR2_LINUX_KERNEL_INTREE_DTS_NAME
+# in ${BR_CONFIG}, then prints the corresponding list of file names for the
+# genimage configuration file
+#
+dtb_list()
+{
+	local DTB_LIST="$(sed -n 's/^BR2_LINUX_KERNEL_INTREE_DTS_NAME="\([a-z0-9 \-]*\)"$/\1/p' ${BR2_CONFIG})"
+
+	for dt in $DTB_LIST; do
+		echo -n "\"$dt.dtb\", "
+	done
+}
+
+#
+# linux_image extracts the Linux image format from BR2_LINUX_KERNEL_UIMAGE in
+# ${BR_CONFIG}, then prints the corresponding file name for the genimage
+# configuration file
+#
+linux_image()
+{
+	if grep -Eq "^BR2_LINUX_KERNEL_UIMAGE=y$" ${BR2_CONFIG}; then
+		echo "\"uImage\""
+	else
+		echo "\"zImage\""
+	fi
+}
+
+main()
+{
+	local FILES="$(dtb_list) $(linux_image)"
+	local GENIMAGE_CFG="$(mktemp --suffix genimage.cfg)"
+	local GENIMAGE_TMP="${BUILD_DIR}/genimage.tmp"
+
+	sed -e "s/%FILES%/${FILES}/" \
+		board/freescale/common/genimage.cfg.template > ${GENIMAGE_CFG}
+
+	rm -rf "${GENIMAGE_TMP}"
+
+	genimage \
+		--rootpath "${TARGET_DIR}" \
+		--tmppath "${GENIMAGE_TMP}" \
+		--inputpath "${BINARIES_DIR}" \
+		--outputpath "${BINARIES_DIR}" \
+		--config "${GENIMAGE_CFG}"
+
+	rm -f ${GENIMAGE_CFG}
+
+	exit $?
+}
+
+main $@