using dd to clear space in Nand flash

 mtd0: 00100000 00020000 "Bootloader"
mtd1: 00040000 00020000 "security"
mtd2: 00800000 00020000 "BP IMAGE"
mtd3: 000c0000 00020000 "NVM"
mtd4: 00040000 00020000 "logo"
mtd5: 00300000 00020000 "Kernel"
mtd6: 06000000 00020000 "system"
mtd7: 03600000 00020000 "userdata"
mtd8: 04000000 00020000 "opl"
mtd9: 00800000 00020000 "local"
mtd10: 008c0000 00020000 "cache"
mtd11: 00600000 00020000 "fota"
mtd12: 00080000 00020000 "panic"

 

try to clear NVM which have two parts, half of it is recording the CP calabration data, the other part is production configures.

 

NVM is messed by using dataIO, the format of it is wrong so using:

 

dd if=/dev/zero of=/dev/mtd/mtd3 bs=2048 count=192

 

to clear it for recover