Boot another OS - help required: old kernel

[kingoddball]

Hi,

I'm working on a different OS project...

Need help with the very first part!!

How do I boot it?

I can boot other os's on pandora, normally it has a kernel which matches the boot.txt.

My kernel image is: zImage-2.6.28.10-power52 (other kernels too, but all are similar name and type). I'm sure many of you know the kernel name from another device.........

I tried a basic cheat of take out "uImage-3" out and insert that but failed due to compression type.

Once I can get a boot to prompt I/we can start to work on the GUI.

I got the OS by going a NAND dump. I have had this OS running on top of Android previously, but I want it to boot standalone.

 

[levi]

A quick search suggests a uImage is a zImage with a 64-bit uboot header prepended. You can apparently use the mkimage tool to convert zImages to uImages, although a quick vgrep of its manpage wasn't enlightening.


Apparently you should be able to boot zimage kernels using uboot, but you need some extra magic on the bootm line, and I don't know which runes you need.

 

[kingoddball]

Thanks!
I don't want to change the current image - Maemo is a pain in the ass.

Can't take a kernel change, will just panic and freakout.

I did have a build environment, but that was a few years back, and it did make uImages.. Time to find my old ones maybe.

Unless someone else has a boot.txt which is setup fro zImage?

.... Yes... Maemo on Open Pandora project  :lol:

And not my old CHROOT.... Native OS!  h34r:

 

[levi]

Hmm, I may have got slightly the wrong information. It seems from this discussion, booting zimage from uboot needs a modified uboot - you need to configure it to enable to bootz command, then replace your bootp command with a bootz one (and possibly tweak the addresses, but hopefully not).


However, I'd expect converting your zimage to a uimage shouldn't cause a problem for the code once running - the files are equivalent once loaded. However, you'll need to figure out how to drive mkimage to do the conversion, and hopefully make your build environment do it automatically.


Or if you wanted to try out a hack, you could rip the front 64 bytes off a pandora UImage and pack than on the front of your zimage and see if that works, from what I understand

 

[kingoddball]

Thanks for your help! It's fine. I have scrapped the zImage idea and now moved to uImage...

I have an idea

I do hope to have a working Maemo build tonight! It would be today, but I left my OP at home.

If (when?? lets hope) I get it running, if anyone is willing to help, please do!

 

[kingoddball]

Hmmm.... Stuck....

I got all the OS files over and seemingly correct but I can't get the kernel to boot.

".... Starting Kernel" or something to that effect.

It's an older 2.6.*** kernel.

It identifies it right when it starts to load, then just fails at starting.

I used a bog standard boot.txt (same one from Ubuntu/Slackware).

I did try get a newer 3.* kernel to work, it booted, but maemo had a fit about setting CPU.