MMC
# echo 0 > /sys/block/mmcblk1boot1/force_ro
ext csd
PARTITION_CONFIG (formerly BOOT_CONFIG)
http://rere.qmqm.pl/~mirq/JESD84-A44.pdf
BOOT_BUS_WIDTH[177]
PARTITION_CONFIG (before BOOT_CONFIG)[179]
# echo 0 > /sys/block/mmcblk1boot1/force_ro
ext csd
PARTITION_CONFIG (formerly BOOT_CONFIG)
http://rere.qmqm.pl/~mirq/JESD84-A44.pdf
BOOT_BUS_WIDTH[177]
PARTITION_CONFIG (before BOOT_CONFIG)[179]