[Shr-User] UBI success story

[Martin Jansa]

On Sat, Dec 26, 2009 at 09:25:57PM +0100, Christoph Mair wrote:
> Hello,
> 
> I tried to use SHR the ubi images on my freerunner, but they did not work. 
> Does someone know the parameters which are passed to mkfs.ubifs? I think that 
> the ubi fileystem is created for NAND flashes with subpage support, but this 
> feature does not work on the freerunner. Passing -s 2048 should create a 
> working image (but I did not verify this yet).

Params are in:
http://git.openembedded.org/cgit.cgi/openembedded/tree/conf/machine/om-gta02.conf

MKUBIFS_ARGS = "-m 2048 -e 129024 -c 2047"
for mkfs.ubifs

UBINIZE_ARGS = "-m 2048 -p 128KiB -s 512"
for ubinize

So I don't see param for subpage setting for mkfs.ubifs, its only in ubinize,
but it didn't help for my NAND, even when I prepare ubi volume on neo with 
-s 2048 -O 2048 and then try to updatevol with full image (small image
like initramfs-kexecboot works for me just fine). That's why I didn't
push patch for setting it in UBINIZE_ARGS.

> Using the ubi filesystem on the freerunner is not an easy task. A ubi image 
> can't be flashed using nandwrite. I'm not sure about dfu-util, but probably it 
> uses the same technique as nandwrite and therefore won't work too. I did a 
> manual installation (untar SHR into a mounted ubifs) using archmobile 
> installed on SD. If the SHR ubi image is created with the right parameters 
> ubiformat or ubiupdatevol could be used to install the image. For a easy 
> installation with dfu-util, u-boot would need support for ubi images.
> 
> I used the newest kernel (om-gta02-2.6.32), but a older one should work too.

I had more issues with kernels older than 2.6.32.

> To fix this, we need to tell the kernel that the mtd partition 6 contains a ubi 
> volume which contains the ubifs rootfs: rootfstype=ubifs ubi.mtd=6,2048 
> root=ubi0:rootfs.
> For a "normal" boot qi passes rootfstype=jffs2 root=/dev/mtdblock6 to the 
> kernel. Just changing the boot params within the kernel configuration does not 
> work. Therefore I patched qi :)

Ah great!, thanks

-- 
uin:136542059                jid:Martin.Jansa at gmail.com
Jansa Martin                 sip:jamasip at voip.wengo.fr 
JaMa