sdcard_image-rpi: Add 1st cut at a class to build an SD card image for the RPi.

2012-04-23 15:16:08 +01:00
parent b0e4ba5f7a
commit 1cc562d9d3
1 changed files with 131 additions and 0 deletions
--- a/classes/sdcard_image-rpi.bbclass
+++ b/classes/sdcard_image-rpi.bbclass
@ -0,0 +1,131 @@
+inherit image
+
+# Add the fstypes we need
+IMAGE_FSTYPES_append = " tar.bz2 rpi-sdimg"
+
+# Ensure required utilities are present
+IMAGE_DEPENDS_rpi-sdimg = "genext2fs-native e2fsprogs-native bcm2835-bootfiles bcm2835-kernel-image"
+
+# Register this as an avalable type of image.
+IMAGE_TYPES_append = " rpi-sdimg"
+
+# Change this to match your host distro
+LOSETUP ?= "/sbin/losetup"
+
+# Since these need to go in /etc/fstab we can hardcode them
+# Since the vars are weakly assigned, you can override them from your local.conf
+LOOPDEV ?= "/dev/loop1"
+LOOPDEV_BOOT ?= "/dev/loop2"
+LOOPDEV_FS ?= "/dev/loop3"
+
+# Default to 4GiB images
+SDIMG_SIZE ?= "444" 
+
+# FS type for rootfs
+ROOTFSTYPE ?= "ext4"
+
+BOOTPARTNAME ?= "${MACHINE}"
+
+IMAGEDATESTAMP = "${@time.strftime('%Y.%m.%d',time.gmtime())}"
+
+# Additional files and/or directories to be copied into the vfat partition from the IMAGE_ROOTFS.
+FATPAYLOAD ?= ""
+
+IMAGE_CMD_rpi-sdimg () {
+	SDIMG=${WORKDIR}/sd.img
+
+	# sanity check fstab entry for boot partition mounting
+	if [ "x$(cat /etc/fstab | grep ${LOOPDEV_BOOT} | grep ${WORKDIR}/tmp-mnt-boot | grep user || true)" = "x" ]; then
+		echo "/etc/fstab entries need to be created with the user flag for the loop devices like:"
+		echo "${LOOPDEV_BOOT} ${WORKDIR}/tmp-mnt-boot vfat user 0 0"
+        false
+	fi
+
+	# cleanup loops
+	for loop in ${LOOPDEV} ${LOOPDEV_BOOT} ${LOOPDEV_FS} ; do
+		${LOSETUP} -d $loop || true
+	done
+
+	# If an SD image is already present, reuse and reformat it
+	if [ ! -e ${SDIMG} ] ; then
+		dd if=/dev/zero of=${SDIMG} bs=$(echo '255 * 63 * 512' | bc) count=${SDIMG_SIZE}
+	fi
+
+	${LOSETUP} ${LOOPDEV} ${SDIMG}
+
+	# Create partition table
+	dd if=/dev/zero of=${LOOPDEV} bs=1024 count=1024
+	SIZE=$(/sbin/fdisk -l ${LOOPDEV} | grep Disk | grep bytes | awk '{print $5}')
+	CYLINDERS=$(echo $SIZE/255/63/512 | bc)
+	{
+	echo ,9,0x0C,*
+	echo ,,,-
+	} | /sbin/sfdisk -D -H 255 -S 63 -C ${CYLINDERS} ${LOOPDEV}
+
+	# Prepare loop devices for boot and filesystem partitions
+	BOOT_OFFSET=32256
+	FS_OFFSET_SECT=$(/sbin/fdisk -l -u ${LOOPDEV} 2>&1 | grep Linux | perl -p -i -e "s/\s+/ /"|cut -d " " -f 2)
+	FS_OFFSET=$(echo "$FS_OFFSET_SECT * 512" | bc)
+	FS_SIZE_BLOCKS=$(/sbin/fdisk -l -u ${LOOPDEV} 2>&1 | grep Linux | perl -p -i -e "s/\s+/ /g" \ 
+	|cut -d " " -f 4 | cut -d "+" -f 1)
+ 
+	LOOPDEV_BLOCKS=$(/sbin/fdisk -l -u ${LOOPDEV} 2>&1 | grep FAT | perl -p -i -e "s/\s+/ /g"|cut -d " " -f 5)
+	LOOPDEV_BYTES=$(echo "$LOOPDEV_BLOCKS * 1024" | bc)
+
+	${LOSETUP} -d ${LOOPDEV}
+
+	${LOSETUP} ${LOOPDEV_BOOT} ${SDIMG} -o ${BOOT_OFFSET} 
+
+	/sbin/mkfs.vfat ${LOOPDEV_BOOT} -n ${BOOTPARTNAME} $LOOPDEV_BLOCKS
+
+	# Prepare boot partion. First mount the boot partition, and copy the bootloader and supporting files.
+
+	mkdir -p ${WORKDIR}/tmp-mnt-boot
+	mount $LOOPDEV_BOOT ${WORKDIR}/tmp-mnt-boot
+
+	echo "Copying bootloader and prepended kernel.img into the boot partition"
+	cp -v ${DEPLOY_DIR_IMAGE}/bcm2835-bootfiles/* ${WORKDIR}/tmp-mnt-boot || true
+
+	if [ -n ${FATPAYLOAD} ] ; then
+		echo "Copying payload into VFAT"
+		for entry in ${FATPAYLOAD} ; do
+				# add the || true to stop aborting on vfat issues like not supporting .~lock files
+				cp -av ${IMAGE_ROOTFS}$entry ${WORKDIR}/tmp-mnt-boot || true
+		done
+	fi
+
+	echo "${IMAGE_NAME}-${IMAGEDATESTAMP}" > ${IMAGE_ROOTFS}/etc/image-version-info
+	
+	cp -v ${IMAGE_ROOTFS}/etc/image-version-info ${WORKDIR}/tmp-mnt-boot || true
+
+	# Cleanup VFAT mount
+	echo "Cleaning up VFAT mount"
+	umount ${WORKDIR}/tmp-mnt-boot
+	${LOSETUP} -d ${LOOPDEV_BOOT} || true
+
+	# Prepare rootfs parition
+	echo "Creating rootfs loopback"
+	${LOSETUP} ${LOOPDEV_FS} ${SDIMG} -o ${FS_OFFSET}
+
+	FS_NUM_INODES=$(echo $FS_SIZE_BLOCKS / 4 | bc)
+
+	case "${ROOTFSTYPE}" in
+		ext3)
+				genext2fs -z -N $FS_NUM_INODES -b $FS_SIZE_BLOCKS -d ${IMAGE_ROOTFS} ${LOOPDEV_FS}
+				tune2fs -L ${IMAGE_NAME} -j ${LOOPDEV_FS}
+				;;
+		ext4)
+				genext2fs -z -N $FS_NUM_INODES -b $FS_SIZE_BLOCKS -d ${IMAGE_ROOTFS} ${LOOPDEV_FS}
+				tune2fs -L ${IMAGE_NAME} -j -O extents,uninit_bg,dir_index ${LOOPDEV_FS}
+				;;
+		*)
+				echo "Please set ROOTFSTYPE to something supported"
+				exit 1
+				;;
+	esac
+
+	${LOSETUP} -d ${LOOPDEV_FS} || true
+
+	gzip -c ${WORKDIR}/sd.img > ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}-${IMAGEDATESTAMP}.img.gz
+	rm -f ${WORKDIR}/sd.img
+}