Thanks Charles.
I would like to explain my problem in detail!
I want to use YAFFS2 as flash file system.
I need to store two stage boot loader in NAND. Stage - 1 bootloader
stored (First 4k code can be loaded in Internal RAM ) in
block 0, which is responsible to copy the stage -2 boot loader
from other portion of the NAND to SDRAM and pass control to it for
execution. Stage - 2 boot loader is responsible initializing
peripherals and booting up kernel image.
Design Approach - 1 : Have separate partitions for Stage -2 boot loader , kernel image and root file system.
Advantage:- kernel images can be loaded using TFTP / FTP support available in boot loader.
Disadvantage:- If only 'n' number of blocks are allocated for loading
kernel image and all the allocated blocks goes bad after some program /
erase cycles then you can not load kernel image again!
Design Approach 2: have two partition boot and root. Bootloader will mount root partition and boot the kernel image!
Advantage:- Kernel image program / erase is not restricted to some partition space!
Disadvantage: - As root file system can be mounted only as read only
from boot loader. I can not reload kernel image from boot loader. I
need to flash entire root file system again!
What efforts are required to mount root file system as read / write from boot loader?
How mkyaffs utility works? How it marks bad block when first time it is used to flash the images
on NAND flash?
--Rakhi
On Thursday 29 September 2005 01:11, Rakhi Rathi wrote:
> Hi All,
>
> Is YAFFS boot loader code available under cvs directory 'direct' supports
> mounting of root file system in read / write mode?
This only allows read mode.
It is intended to support reading a boot image file, that is all.
-- Charles