CODEWITHSUNDEEP
linuxmemory-managementfirmware
Praveen
Praveen

Reputation: 75

Understanding embedded platform design

I am trying to understand the different Linux Memory Design choices. I am working on an embedded ARM/Linux platform (beginner).

The firmware is loaded on to the flash it contains kernel and rootfs. The whole image is loaded on to the RAM during boot-up.

What are the advantages of this design choice ? are there any alternatives ? How is it different from Evaluation boards like Beagle Bone Black ?

Thanks in advance

Upvotes: 0

Views: 78

Answers (1)

shri
shri

Reputation: 874

Normally the flash can be used to have the boot program, kernel image and the rootfs. Mostly Linux run from RAM instead of Flash, because it is usually faster while running from RAM. Hence during the boot process the kernel tt is copied from Flash into RAM by U-Boot. The other option is the bootloader extracts the compressed kernel from the flash into the SDRAM, and then kernel mounts the rootfs.

Most of the embedded system uses intramfs,since memory is a constrain in embedded system. Pl refer this link for more details on this https://unix.stackexchange.com/questions/27309/how-do-i-have-linux-boot-with-a-rootfs-in-ram

Apart from this,Most distributions used compressed ext2 file system images, while the others like Debian 3.1 used cramfs in order to boot on memory-limited system. cramfs image does not require extra space for decompression.

Upvotes: 1

Related Questions