Forums » Software Development »
Creating a small basic system
Added by Keith Fletcher over 11 years ago
Hi I am attempting to create a basic filesystem, that is small enough to fit on the NAND, however the link provided in the Root Filesystem Wiki Page (Installing Open Embedded) goes to a non-existant page. I tried using the ARM9 wiki as a guide, but got well confused, mainly because I could find an Open embeded overlay directory for the MityARM-335x.
Any suggestions on where I can found out how to do this (or where I can get a basic root fs for the mityArm-335x from).
Thanks,
Keith.
Replies (4)
RE: Creating a small basic system - Added by Tim Iskander over 11 years ago
Keith,
There are a few different ways to go about this...
- We have a smaller base FS I can get you. The catch is that it has not been thoroughly vetted. It should be fine, but it was built with a newer toolchain, etc and it has not had a lot of testing/use yet.
- You can remove packages from the existing devkit filesystem until you get one you like (admittedly not the best approach)
- Timesys (www.timesys.com) is in the process of adding the MityARM-335x to its linuxlink tool. Once this happens you will be able to build a filesystem using their web tools. This is the (IMHO) preferred approach, but is still a couple of weeks away.
hope this helps, let me know if you would like to try the newer CL filesystem.
cheers
/Tim
RE: Creating a small basic system - Added by Michael Williamson over 11 years ago
Hi Keith,
I updated the wiki about building a rootfs from scratch with open embedded and posted some files (SDKs and a couple of filesystems) that you might try if you are stuck and can't wait for Timesys to come online.
We haven't done a whole lot of "smoke testing" with these images beyond see that they boot, so your mileage may vary.
-Mike
RE: Creating a small basic system - Added by Keith Fletcher over 11 years ago
Hi Tim and Mike,
Thanks for your help with the filesystems - I grabbed one of the the new small filesystems from the Wiki and attempted to use it from NAND.
I followed the processes in the TI documents, UBIFS Support and AM335x U-Boot User's Guide to generate an ubifs.img and then a ubi.img for NAND
( had to upgrade the VM Ubunta mtd-utils with the latest version, using a debian package, rather than the Ubunta upgrade facility).
The file generated without errors.
However, when I attempt to load it I get the following errors:
[ 1.799736] VFS: Cannot open root device "ubi0:rootfs" or unknown-block(0,0)
[ 1.807119] Please append a correct "root=" boot option; here are the available partitions:
[ 1.815872] 1f00 8192 mtdblock0 (driver?)
[ 1.821144] 1f01 128 mtdblock1 (driver?)
[ 1.826430] 1f02 128 mtdblock2 (driver?)
[ 1.831700] 1f03 128 mtdblock3 (driver?)
[ 1.836979] 1f04 128 mtdblock4 (driver?)
[ 1.842252] 1f05 1920 mtdblock5 (driver?)
[ 1.847532] 1f06 128 mtdblock6 (driver?)
[ 1.852802] 1f07 5120 mtdblock7 (driver?)
[ 1.858085] 1f08 254464 mtdblock8 (driver?)
[ 1.863362] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
[ 1.871972] Backtrace:
And if I try to attach to it from the SD card:
root@mityarm-335x:~# ubiattach /dev/ubi_ctrl -m 7 -O 2048
[ 1407.972361] UBI: attaching mtd7 to ubi0
[ 1407.976378] UBI: physical eraseblock size: 131072 bytes (128 KiB)
[ 1407.982979] UBI: logical eraseblock size: 126976 bytes
[ 1407.988603] UBI: smallest flash I/O unit: 2048
[ 1407.993513] UBI: sub-page size: 512
[ 1407.998322] UBI: VID header offset: 2048 (aligned 2048)
[ 1408.004614] UBI: data offset: 4096
[ 1408.044622] UBI: max. sequence number: 0
[ 1408.049268] UBI error: ubi_read_volume_table: the layout volume was not found
ubiattach: error!: cannot attach mtd7
error 22 (Invalid argument)
But also from the SD card, if I try to mount the mtd file directly I get:
root@mityarm-335x:~# mount -t ubifs ubi0:rootfs /media/card
mount: unknown filesystem type 'ubifs'.
My concern is that the kernel provided may not have ubifs filesystem support. Is that possible ?
Regards
Keith.
RE: Creating a small basic system - Added by Michael Williamson over 11 years ago
Hi Keith,
It's quite possible that the images I posted (built from openembedded / Angstrom reference images) don't have ubifs support. I only booted the images via NFS to "smoke-test" them and haven't tried booting them out of FLASH (or SD for that matter). Sorry if I mislead you.
The kernel configuration used should match the one from the SD card delivered with the DevKit, but you should be able to check /proc/config.gz (using cat /proc/config.gz | gzip -d > /tmp/config.txt or something similar) to check for UBIFS support.
I will check the packages that included with the reference filesystems tomorrow for ubifs. If you are on the network you might be able to do an opkg update and install the needed packages from the openembedded feeds. If I get a couple of minutes tomorrow, I'll see if Tim or I can walk through flashing up the NAND here and booting from it using the smaller OS image and get the details posted on the wiki here.
Again, sorry for the headaches.
-Mike
