Hi there,

I'd appreciate your patience, as this may sound like a dumb question. I've just started working with ARM processors (AT91SAM9261-EK) and Linux within the last three weeks, previously I've only worked on 16-bit and 8-bit micros.

Anyway, I've sucessfully built my own 2.6.21 kernel. I followed the kernel compilation guide on arm.linux.org, and got a uImage kernel, together with the modules.

Now this is where I'm struggling.

My kernel command line is "mem=64M console=ttyS0,115200 initrd=0x21100000,3145728 root=/dev/ram0 rw"

I've successfully unzipped and booted the kernel on my target board. But I'm lacking the RAM disk image and I get:

RAMDISK: Couldn't find valid RAM disk image starting at 0.
No filesystem could mount root, tried: ext2
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(1,0)

So (and this is where I probably sound stupid) how do I make RAMDISK? Is this file system built using mkfs.ext2 /dev/ram0, because I did that but can't find any output image!

Alternatively, can I mount a complete FLASH file system immediately using all my compiled modules, or do I have to install initrd first

I'd appreciate any pointers. Particularly suggestions for mkfs commands, and corresponding kernel command lines.

Incidentally, I don't want to use Buildroot since I want to get a real understanding of the low-level operation of the system. Plus I tried it and just got a massive string of "undefined reference" errors

Thanks in advance,
Timmins

EDIT: I've googled my ar$e off looking for a file system/kernel init guide to no avail. Just so you know!

Have you already use the board with the FS provided by ATMEL?

When you use SAMBA, a FS image is put on the SPI flash or NAND flash and when you boot, Uboot copy this FS on the RAM. So I think that it is the best way if you are a beginner and if you search to create your own kernel because FS is not really the most important in the begin ...

Pierre

Thanks for your reply, I got the rfs to mount, and got as far as the busybox console. I have a couple of errors, presumably because I haven't installed my modules yet:



I've compiled my modules into a JFFS2 system, now I've got to try to get this working too... I'll probably be back for help shortly!

Thanks,
Timmins

I got exactly your problem Kernel OK but ramdisk not working with errors in mounting ...

please could you give me more details on how to use samba disk ?

do you have a working .config file for 2.6.20 and a working ramdisk ?

thank you very much

hi Timmins...
i m facing the same problem ....i hope till nw u hav already solved ur problem.
plzzz fwd me ur solution....plz plz help me out..!!!
thanksss

you have to create a proper ramdisk image

Howto create a ramdisk
Make a RAMDisk for the Filesystems
Before you can load your filesystems onto our target board, you must first create a RAMDisk of the file systems:
http://www.koansoftware.com/it/art.php?art=104