sdcard_image-rpi.bbclass: Rewrite sdimage creation class - implemented with parted

This implementation doesn't use loop mounts, it uses mcopy to copy files to partitions.
The partition creation is done with parted. Because of using these tools the
IMAGE_DEPENDS was modified accordingly.
Added a way of selecting the desired GPU firmware.
Because we don't create the rootfs image but we rely on an already created rootfs
image, the stamp is available only in the boot partition.
By default the class needs an ext3 rootfs image. This is because we don't have yet
a way of generating cmdline.txt in order to pass the partition type to the kernel.
By default ext3 is mounted so we use this fs type until this will be selectable while
generating a cmdline file.

Signed-off-by: Andrei Gherzan <andrei@gherzan.ro>

1 files changed, 81 insertions, 113 deletions

diff --git a/classes/sdcard_image-rpi.bbclass b/classes/sdcard_image-rpi.bbclass
index 1ac3e84..ef27ac6 100644
--- a/classes/sdcard_image-rpi.bbclass
+++ b/classes/sdcard_image-rpi.bbclass
@@ -1,131 +1,99 @@
-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())}"
+#
+# Create an image that can by written onto a SD card using dd.
+#
+# The disk layout used is:
+#
+#    0  - 1M                  - reserved for other data
+#    1M - BOOT_SPACE          - bootloader and kernel
+#    BOOT_SPACE - SDIMG_SIZE  - rootfs
+#
+
+inherit image_types
+
+# Set kernel and boot loader
+IMAGE_BOOTLOADER ?= "bcm2835-bootfiles"
+
+# Default to 1.4GiB images
+SDIMG_SIZE ?= "4000"
+
+# Boot partition volume id
+BOOTDD_VOLUME_ID ?= "${MACHINE}"
+
+# Addional space for boot partition
+BOOT_SPACE ?= "20MiB"
+
+# Use an ext3 by default as rootfs
+SDIMG_ROOTFS_TYPE ?= "ext3"
+SDIMG_ROOTFS = "${IMAGE_NAME}.rootfs.${SDIMG_ROOTFS_TYPE}"
+
+# Set GPU firmware image to be used
+# arm128 : 128M ARM, 128M GPU split
+# arm192 : 192M ARM, 64M GPU split
+# arm224 : 224M ARM, 32M GPU split
+RPI_GPU_FIRMWARE ?= "arm192"
+
+IMAGE_DEPENDS_rpi-sdimg = " \
+                        parted-native \
+                        mtools-native \
+                        dosfstools-native \
+                        virtual/kernel \
+                        ${IMAGE_BOOTLOADER} \
+                        "
+
+# SD card image name
+SDIMG = "${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.rpi-sdimg"
 
 # 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
+IMAGEDATESTAMP = "${@time.strftime('%Y.%m.%d',time.gmtime())}"
 
-        ${LOSETUP} ${LOOPDEV} ${SDIMG}
+IMAGE_CMD_rpi-sdimg () {
+        # Initialize sdcard image file
+        dd if=/dev/zero of=${SDIMG} bs=1 count=0 seek=$(expr 1000 \* 1000 \* ${SDIMG_SIZE})
 
         # 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
+        parted -s ${SDIMG} mklabel msdos
+        # Create boot partition and mark it as bootable
+        parted -s ${SDIMG} mkpart primary fat32 1MiB ${BOOT_SPACE}
+        parted -s ${SDIMG} set 1 boot on
+        # Create rootfs partition
+        parted -s ${SDIMG} mkpart primary ext2 ${BOOT_SPACE} 100%
+        parted ${SDIMG} print
+
+        # Create a vfat image with boot files
+        BOOT_BLOCKS=$(LC_ALL=C parted -s ${SDIMG} unit b print | awk '/ 1 / { print substr($4, 1, length($4 -1)) / 512 /2 }')
+        mkfs.vfat -n "${BOOTDD_VOLUME_ID}" -S 512 -C ${WORKDIR}/boot.img $BOOT_BLOCKS
+        case "${RPI_GPU_FIRMWARE}" in
+                "arm128" | "arm192" | "arm224")
+                        mcopy -i ${WORKDIR}/boot.img -s ${DEPLOY_DIR_IMAGE}/bcm2835-bootfiles/${RPI_GPU_FIRMWARE}_start.elf ::start.elf
+                        ;;
+                *)
+                        bberror "RPI_GPU_FIRMWARE is undefined or value not recongnised. Possible values: arm128, arm192 or arm224."
+                        exit 1
+                        ;;
+        esac
 
-        echo "Copying bootloader and prepended kernel.img into the boot partition"
-        cp -v ${DEPLOY_DIR_IMAGE}/bcm2835-bootfiles/* ${WORKDIR}/tmp-mnt-boot || true
+        # To do
+        # Copy here a cmdline.txt file generated taking into consideration the partition type
+        # of the rootfs
+        mcopy -i ${WORKDIR}/boot.img -s ${DEPLOY_DIR_IMAGE}/bcm2835-bootfiles/bootcode.bin ::
+        mcopy -i ${WORKDIR}/boot.img -s ${DEPLOY_DIR_IMAGE}/bcm2835-bootfiles/loader.bin ::
+        mcopy -i ${WORKDIR}/boot.img -s ${DEPLOY_DIR_IMAGE}/bcm2835-bootfiles/kernel.img ::
 
         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
+                                mcopy -i ${WORKDIR}/boot.img -s -v ${IMAGE_ROOTFS}$entry :: || 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 ${LOOPDEV_FS} || true
+        # Add stamp file
+        echo "${IMAGE_NAME}-${IMAGEDATESTAMP}" > ${WORKDIR}/image-version-info
+        mcopy -i ${WORKDIR}/boot.img -v ${WORKDIR}//image-version-info ::
 
-        gzip -c ${WORKDIR}/sd.img > ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}-${IMAGEDATESTAMP}.img.gz
-        rm -f ${WORKDIR}/sd.img
+        # Burn Partitions
+        dd if=${WORKDIR}/boot.img of=${SDIMG} conv=notrunc seek=1 bs=1M && sync && sync
+        dd if=${SDIMG_ROOTFS} of=${SDIMG} conv=notrunc seek=1 bs=${BOOT_SPACE} && sync && sync
 }