6 Software
User Manual 71/374
6.5.1 NOR Flash
Low Level Hardware Access
This character device includes the interface to the root file
system "(root) /".
This character device includes the interface to the kernel
image.
This character device includes the interface to the U-Boot.
This character device includes the interface to the U-Boot
environment variables.
This character device includes the interface to the flattened
device tree (FDT).
This character device includes the interface to a reserved
part of the FDT (/dev/mtd4).
This character device includes the interface to the nand-
flash.
Example: Read memory information
Read memory information from /dev/mtd0 by using /usr/sbin/mtdinfo
# mtdinfo /dev/mtd0
mtd0
Name: rootfs
Type: nor
Eraseblock size: 131072 bytes, 128.0 KiB
Amount of eraseblocks: 440 (57671680 bytes, 55.0 MiB)
Minimum input/output unit size: 1 byte
Sub-page size: 1 byte
Character device major/minor: 90:0
Bad blocks are allowed: false
Device is writable: true
Do not use the NOR flash for data storage.
Due to the limited number of writing cycles, it is highly recommended to use the NOR flash either in
read-only mode or activate the overlay mechanism to gain the NOR flash's lifetime.