Okay, then
1. boot form sata to Uboot
2. load your uboot-backup via tftp
3. write it back to nand:
Same for stage1:
Powerdown the nas & remove the disk
If you did not backuped your uboot or stage1 here you can get them
stage1.backup
uboot.backup
1. boot form sata to Uboot
2. load your uboot-backup via tftp
tftp 64000000 uboot.backup # <- your backup file former mtd2
3. write it back to nand:
nand erase 40000 200000 nand write 64000000 40000 200000
Same for stage1:
tftp 64000000 stage1.backup nand erase 0 40000 nand write 64000000 0 40000
Powerdown the nas & remove the disk
If you did not backuped your uboot or stage1 here you can get them
stage1.backup
uboot.backup