Add mkelfimage and support for generating kernel+initrd ELF payloads to OpenEmbedded

On x86, and ELF image file may be stored as a coreboot payload. This image file may be a kernel or a kernel+initrd.

Documentation on this has been started on the coreboot wiki:
http://www.coreboot.org/Mkelfimage

We have seen success using the mkelfimage utility to construct a kernel+initrd image using the micro-image OpenEmbedded image as an initrd.
http://www.se-eng.com/wiki/index.php/Open_Embedded_Setup

The second patch contains the necessary commands for adding the image type to bitbake.

---
  conf/bitbake.conf |    3 +++
  1 files changed, 3 insertions(+), 0 deletions(-)

conf/bitbake.conf +1 -0

index 66dfaba..1ab72e1 100644
@@ -375,6 +375,7 @@ IMAGE_BASENAME = "${PN}"
  IMAGE_NAME = "${IMAGE_BASENAME}-${MACHINE}-${DATETIME}"
  IMAGE_LINK_NAME = "${IMAGE_BASENAME}-${MACHINE}"
  IMAGE_EXTRA_SPACE = 10240
+IMAGE_KERNELPARAMS = "ramdisk_size=32768 root=/dev/ram0 rw console="
 
  UBI_VOLNAME ?= "${MACHINE}-rootfs"
 

@@ -406,6 +407,7 @@ IMAGE_CMD_cpio.gz.u-boot = "type cpio >/dev/null; cd 

${IMAGE_ROOTFS} && (find .
IMAGE_CMD_cpio.lzma = "type cpio >/dev/null; cd ${IMAGE_ROOTFS} &&
(find . | cpio -o -H newc | xz --format=lzma -c ${XZ_COMPRESSION_LEVEL} --check=${XZ_INTEGRITY_CHECK}

Quoted 1 line

${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.cpio.lzma) ${EXTRA_IMAGECMD}"

IMAGE_CMD_ubi = "echo \[ubifs\] > ubinize.cfg ; echo mode=ubi >>
ubinize.cfg ; echo image=${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.ubifs.img >> ubinize.cfg ; echo vol_id=0 >> ubinize.cfg ; echo vol_type=dynamic >> ubinize.cfg ; echo vol_name=${UBI_VOLNAME} >> ubinize.cfg ; echo vol_flags=autoresize >> ubinize.cfg;mkfs.ubifs -r ${IMAGE_ROOTFS} -o ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.ubifs.img ${MKUBIFS_ARGS} && ubinize -o ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.ubi ${UBINIZE_ARGS} ubinize.cfg"
IMAGE_CMD_ubifs = "mkfs.ubifs -r ${IMAGE_ROOTFS} -o
${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.ubifs.img ${MKUBIFS_ARGS}" +IMAGE_CMD_elf = "type cpio >/dev/null; cd ${IMAGE_ROOTFS} && (find . | cpio -o -H newc | gzip -c -9

Quoted 1 line

${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.cpio.gz) ; rm -f

${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.elf ; mkelfImage --append='${IMAGE_KERNELPARAMS}' --kernel=${STAGING_DIR}/${MACHINE}${HOST_VENDOR}-${HOST_OS}/kernel/bzImage --initrd=${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.cpio.gz --output=${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.elf ${EXTRA_IMAGECMD}"

EXTRA_IMAGECMD = ""
EXTRA_IMAGECMD_jffs2 = ""