Flashing NAND from NAND

[Joachim Ott]

2009/10/20 Matthias Huber <matthias.huber at wollishausen.de>:
> Joachim Ott schrieb:
>
> 2009/10/20 Matthias Huber <matthias.huber at wollishausen.de>:
>
>
> ...
> just for clearness: is the boot - partition different from the rootfs ?
> and how are the other partitions ?
>
>
> /dev/mtd0 is the 2 MB NOR flash that contains the NOR bootloader
>
> /dev/mtd1 - mtd6 are the 256 MB NAND flash, the names and sizes are
> shown when the kernel boots (check "dmesg | more" after boot) and they
> contain:
>
> - u-boot or Qi
> - u-boot environment
> - kernel
> - splash image shown directly after power on
> - factory settings
> - rootfs
>
>
>
> my question was thougt as: do the other partitions also have to be erased ?
>
> on the mounted rootfs (/dev/mtdblock6) i am writing just normal without
> erasing, thats why i am stating this question.

There's a difference between flashing a partition and writing to a
mounted filesystem. When you edit a file and change only one byte, the
whole block containig this changed byte will be erased and newly
written. This happens transparent to you.

> and what is then the difference between /dev/mtd6 and /dev/mtdblock6 ?

/dev/mtd6 is accessed as char device, while /dev/mtdblock6 is accessed
as block device. See e.g.
http://en.wikipedia.org/wiki/Device_file_system#Devices