Re: qemu: arm: mounting ubifs using nandsim on busybox

From: Pintu Agarwal
Date: Thu Jun 10 2021 - 08:52:43 EST

On Wed, 9 Jun 2021 at 23:52, Richard Weinberger <richard@xxxxxx> wrote:
> Pintu,
> ----- Ursprüngliche Mail -----
> > Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(31,0)
> > =============================
> >
> > If any one has used nandsim on qemu before, please let us know the exact steps.
> nandsim works as expected. It creates a new and *erased* NAND for you.
> So you have no UBI volumes. Therfore UBIFS cannot be mounted.
> I suggest creating a tiny initramfs that creates UBI volumes before mounting UBIFS on
> one of the freshly created (and empty) volumes.
oh sorry I forgot to mention this.
I am able to create and update volumes manually after booting the
system with initramfs.
Creating rootfs volume:
mknod /dev/ubi0 c 250 0
mknod /dev/ubi0_0 c 250 1
ubiattach /dev/ubi_ctrl -m 2
ubimkvol /dev/ubi0 -N rootfs -m
ubiupdatevol /dev/ubi0_0 ubifs-rootfs.img
mount -t ubifs ubi0:rootfs ubi-root/

But I wanted to do all these automatically during boot time itself.
Also I wanted to use ubinize.cfg as is from the original system and
simulate everything using qemu and nadsim (if possible)
So I thought it must be possible by setting some parameters in qemu such as:
-device nand,chip_id=0x39,drive=mtd0,
-drive if=mtd,file=./ubi-boot.img,id=mtd0,
anything else ?

Or maybe do something at the boot time itself to load the volume image ?
If there are some possibilities please let me know.
With this I can use my original setup as it is and verify everything
with different kernel versions.