Hello,
I'm studing the process performed by MFG Tools to partition, format and installing the Android firmware on a eMMC device.
Looking at the mksdcard-android.sh script, I see the following:
# call sfdisk to create partition table
# get total card size
seprate=40
total_size=`sfdisk -s ${node}`
total_size=`expr ${total_size} / 1024`
boot_rom_sizeb=`expr ${BOOT_ROM_SIZE} + ${BOOTLOAD_RESERVE}`
extend_size=`expr ${SYSTEM_ROM_SIZE} + ${CACHE_SIZE} + ${VENDER_SIZE} + ${MISC_SIZE} + ${seprate}`
data_size=`expr ${total_size} - ${boot_rom_sizeb} - ${RECOVERY_ROM_SIZE} - ${extend_size} + ${seprate}`
# destroy the partition table
dd if=/dev/zero of=${node} bs=1024 count=1
# create partitions
sfdisk --force -uM ${node} << EOF
,${boot_rom_sizeb},83
,${RECOVERY_ROM_SIZE},83
,${extend_size},5
,${data_size},83
,${SYSTEM_ROM_SIZE},83
,${CACHE_SIZE},83
,${VENDER_SIZE},83
,${MISC_SIZE},83
EOF
Can someone explain the meaning the additional ${seprate} with size of 40MB, added to both extended and data partition?
Doing this way, the partitioning exceed the total size of storage device.
This is also reported by logs generated by the target when MFG Tools are partitioning the device:
Disk /dev/mmcblk0: 238592 cylinders, 4 heads, 16 sectors/track
sfdisk: ERROR: sector 0 does not have an msdos signature
/dev/mmcblk0: unrecognized partition table type
Old situation:
No partitions found
Warning: given size (6392) exceeds max allowable size (6352)
New situation:
Units = mebibytes of 1048576 bytes, blocks of 1024 bytes, counting from 0
Device Boot Start End MiB #blocks Id System
/dev/mmcblk0p1 0+ 15 16- 16383+ 83 Linux
/dev/mmcblk0p2 16 23 8 8192 83 Linux
/dev/mmcblk0p3 24 1103 1080 1105920 5 Extended
/dev/mmcblk0p4 1104 7495 6392 6545408 83 Linux
/dev/mmcblk0p5 24+ 535 512- 524287+ 83 Linux
/dev/mmcblk0p6 536+ 1047 512- 524287+ 83 Linux
/dev/mmcblk0p7 1048+ 1055 8- 8191+ 83 Linux
/dev/mmcblk0p8 1056+ 1063 8- 8191+ 83 Linux
Warning: partition 4 extends past end of disk
Successfully wrote the new partition table
Re-reading the partition table ...
mmcblk0: p1 p2 p3 < p5 p6 p7 p8 > p4
mmcblk0: p4 size 13090816 extends beyond EOD, truncated
