HOWTO: Change, remove or add u-boot on power kernel image
 

This is my simple guide to modify power kernel v45 image and to change or remove u-boot from it.

It needs a linux pc (or you can use N900 itself) do some steps.
With some modifications steps can be adapted to windows systems too

How-to remove u-boot:

1. Download power kernel deb file from repository and extract fiasco image from it
2. Unpack Fiasco image
   flasher-3.5 -u -F zImage-2.6.28-maemo45.fiasco
3. Remove u-boot from kernel image (starting read at offset 0x40000 aka 512 blocks)
   dd if=zImage of=uImage_pow45_noUBoot skip=512
4. Remove uImage header from kernel file to obtain a flashable zImage kernel
   dd ibs=64 if=uImage_pow45_noUBoot of=zImage_pow45_noUBoot skip=1
5. Flash new kernel to device
   sudo flasher-3.5 -f -k zImage_pow45_noUBoot -R

How-to change u-boot with Matan's version:

1. Download power kernel deb file from repository and extract fiasco image from it
2. Download Matan's u-boot from repository (it is named u-boot-for-power-kernel) and extract file image from it
3. Unpack Fiasco image
   flasher-3.5 -u -F zImage-2.6.28-maemo45.fiasco
4. Remove u-boot from kernel image (starting read at offset 0x40000 aka 512 blocks)
   dd if=zImage of=zImage_pow45_noUBoot skip=512
5. Copy u-boot to destination zImage
   cp u-boot.bin.0x38000 zImage_pow45_MatanUBoot
6. Add power kernel at end of previous file (starting write at offset 0x38000 aka 448 blocks)
   dd if=zImage_pow45_noUBoot of=zImage_pow45_MatanUBoot seek=448
7. Flash new kernel to device
   sudo flasher-3.5 -f -k zImage_pow45_MatanUBoot -R

ATTENTION: Actual Matan's u-boot can have problems with HW revision different from v2101

How-to add u-boot Matan's version:

1. Download power kernel deb file from repository and extract fiasco image from it
2. Download Matan's u-boot from repository (it is named u-boot-for-power-kernel) and extract file image from it
3. Unpack Fiasco image
   flasher-3.5 -u -F zImage-2.6.28.10-power48.fiasco
4. Transform zImage in uImage (necessary because u-boot boots Kernel only in uImage file format)
   mkimage -A arm -O linux -T kernel -C none -a 80008000 -e 80008000 -n "Power Kernel v48" -d zImage uImage
5. Copy u-boot to destination zImage
   cp u-boot.bin.0x38000 zImage_pow48_MatanUBoot
6. Add power kernel uImage at end of previous file (starting write at offset 0x38000 aka 448 blocks)
   dd if=uImage of=zImage_pow48_MatanUBoot seek=448
7. Flash new kernel to device
   sudo flasher-3.5 -f -k zImage_pow48_MatanUBoot -R

ATTENTION: Actual Matan's u-boot can have problems with HW revision different from v2101

Re: HOWTO: Change or remove u-boot on power kernel image
 

It might be worth mentioning that uninstalling power kernel v45 and installing v42 is also an option.

http://wiki.maemo.org/Kernel_Power#Deinstallation

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

Added guide to add u-boot on power-kernel v46

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

Hey

Is it possible to install v45 via apt-get to device.
I just wanted to test meegon and figured out that v46 does not have u-boot anymore :)

Re: HOWTO: Change or remove u-boot on power kernel image
 

It might also be worth mentioning that you would miss a couple of patches and fixes other than uboot when downgrading from v45 to v42. :D

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

If you're flashing from onboard the device, instead of running this as root:
You do:
The "-R" is optional in both. It just tells your device to reboot right after flashing. This is somewhat safer because in case your N900 has a battery problem or runs out of power or crashes soon after, it might not be able to actually write the changes to disk. (In Linux, the kernel sometimes waits, keeping changes to disk in memory, instead of writing it to disk immediately. When it reboots, it will write every change not yet made to disk before shutting everything down.) However, if you don't immediately need or want to reboot, you can just run "sync", which does just that - writes all the not-yet-written-to-disc-changes to disk. Then you can rest soundly knowing your flashed kernel is saved, so you can reboot at leisure.

- Edit -

Didn't actually say this first time around so: Thanks for posting this in a single concise how-to. I suspect this information was lying around in various places, but it's always nice to see people making clear instructions.

Also, I haven't tried this one, but I thought I'd point out that e-yes (one of the NITDroid developers) created a patch for uboot that makes it boot the attached kernel if you boot with keyboard closed, and takes you to the normal uboot loader screen with the countdown if you boot with keyboard slid out.
Thread - first post on this page: http://talk.maemo.org/showthread.php?t=64921&page=10
Post itself: http://talk.maemo.org/showpost.php?p...1&postcount=91

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

This patch is included in the u-boot-for-power-kernel package.

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

Oh. Was this in power44? I never noticed, but then again I was on Power44 maybe 4-5 days and then power45 came out. Thanks for correcting me on that.

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

Yay, fun stuff:

Followed instructions of adding uboot to Power 46. Downloaded the respective files and extracted u-boot.bin.0x38000 and zImage-2.6.28-maemo46.fiasco images. Used flasher-3.5 to extract the, well, whatever was in there, from the zImage-2.6.28-maemo46.fiasco image. It put out one file, a "zImage". I ran it again just to make sure, it put out the same file, so I figured everything was correct. This was on a Windows Vista 32 bit laptop.

Plugged in N900, copied both the uboot.bin.0x38000 and zImage files on board. (I then remembered the u-boot-for-power-kernel package installed a uboot.bin.0x38000 file into the /usr/lib/uboot.bin/0x38000/ directory. ls -l showed the files as being the same size, so there was no reason to think that the file I got out of that package's source .tar.gz was any different.) Okay, so, I copied uboot.bin.0x038000 to a file I called "u-boot.power46". (Since I've used Matan's "my.u-boot.power41[a/d]" images, I had deduced the name didn't matter.) Then I ran the dd command above, with "of=u-boot.power46" being the only difference. (This was all done in the directory the files were in, so I don't think that should've been any issue.)

From here, I used fiasco-flasher, instead of the softupd -D / flasher combo. Because out of the two, fiasco-flasher, if you have it, is just faster for flashing kernel, and as far as I know does the same exact thing. At any rate, result? I reboot, and it loads uboot - even though I have the keyboard in, the uboot menu does the countdown. Then it does the normal looking-for-kernel-on-SD-card thing. Doesn't have one (I don't have one there, so so far so good), and then it reports that the format of the kernel image is wrong, so it can't boot. "run noloboot", predictably, reports the same error.

So it stays in uboot. The white LED stays on indefinitely. If there's a way to shutdown from uboot directly, I don't know it. So eventually I had to just pull the battery. Which to me is unpleasant but something I knew I was signing up for when I started mucking with kernel flashing. I know how to reflash, not too much of an issue. So I figured I'll go reflash to the just-previously-working power46 kernel (using the same zImage-2.6.28-maemo46.fiasco image I originally extracted my zImage to make the uboot one from). Did that from my Windows laptop - no problem, it flashed. However, even that's not loading now. It takes me to the white Nokia screen, and just sits there. Just like with the non-working uboot just beforehand. White LED stays on, white nokia screen stays on.

Right now I'm gonna test by trying to flash just kernel from stock global pr1.3 fiasco image. I suspect I either got a messed up version of the power46 zImage, or the zImage flasher extracted from that got messed up. If so, it's probably PeaZip's fault, because that's the archive manager I used to get the image out of the .deb on Windows.

If that doesn't work, I'll try for an entire fiasco-image reflash. Not my idea of fun, restoring all my programs afterwords, but, again, something I don't mind doing because I knew I was signing up for that when I fiddle with custom kernel images.

What I am REALLY worried about though, is that somehow, I screwed up the NAND chip itself, or the bootloader on it. In which case I suppose necessity will dictate I spend the time to figure out how to fix that. Anyway, I'll report if even a stock kernel reflash doesn't work. At that point, suggestions will be welcome, especially if the full fiasco-image reflash doesn't work either.

- Edit -

*Sigh of relief*

Extracted zImage from the stock Global firmware fiasco image. It worked. I'm assuming it was just something messed up in the power46 fiasco image or the extracted zImage I got.

Emboldened by things working again, I prepare to attempt to do the same thing all over again. I'm supposing that I should be able to use the N900's available tools to extract the image from the power-kernel deb onboard.

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

There is indeed a problem in the instructions. u-boot expects a uImage, not a zImage. power46 is u-boot-less, so its image is not a uImage. This is just a few bytes added at the start of the image, telling u-boot about its size, purpose, etc.

So indeed, of the three operations in the original post, only the middle one - replacing one u-boot with another will work. The others need an extra step of converting between uImage and zImage.

You can find a mkimage binary (for x86_64 linux) here:
http://my.svgalib.org/770/n900/u-boot/
and instructions for converting a zImage to a uImage here:
http://al.robotfuzz.com/~al/maemo/u-boot/

Re: HOWTO: Change or remove u-boot on power kernel image
 

well, thats what changelogs are for.

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

Matan, is that binary for arm? Downloading it to the N900, making executable, and running, results in error:
(I moved it to sbin and run it from there, in case it makes any difference.)

Also, the instructions say to use "-a 80008000" and "-e 80008000" options. Is this still valid since your uboot in the u-boot-for-power-kernel package is padded to just 0x38000 instead of 0x40000?

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

Does u-boot change the bootloader section of the NAND memory in N900 any way? (/dev/mtd0)

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

Fixed "How-to add u-boot Matan's version:" guide adding the missing step

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

NoLo bootloader (/dev/mtd0) is not modified in no way.

This is a chainloading method to start u-boot without removing old bootloader.
NoLo loads a fake zImage kernel image which contains u-boot plus a kernel (in uImage format) and runs this image.
So NoLo really starts-up u-boot which then starts-up kernel (already loaded in memory)

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

Fixed "How-to remove u-boot:" guide also

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

Hi!
I have tested meego 1.2 and for this, i also have installed uboot. now i dont want to test meego anymore, but i dont know how i can remove uboot. can anyone help me with this problem without reflashing? as far as i know i dont have power kernel installed, its still the original kernel.

*edit*
if i try it with apt-get remove uboot-pr13 it tells me that its not installed.

with apt-cache search uboot i found 2 entries: uboot-mkimage and uboot-power-46 with the message below it:
to remove this again, "apt-get install --reinstall kernel-power kernel-power-flasher" and reboot. does it mean that i have the power kernel installed? should i try this command? and whats the power kernel? Sorry for my stupid questions ;)

*edit* if i enter the mentioned command, it tells me that after it 10mb of additional space will be used. sounds strange to me. please help!

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

i found the solution for my problem. it was:
"apt-get install --reinstall kernel kernel-flasher"

now i dont see the penguin anymore.

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

I've been trying to do this with the power46wl kernel but the device never boots. It shows the little penguin, u-boot times out, the correct kernel is shown, it says linux kernel uncompressed the size and all that but it stays on "loading kernel" forever. I tried both matan's u-boot and one I compiled myself with the instructions here http://elektranox.org/n900/kernel/uboot.html and also the method mentioned in this thread and the builder.py in the link but nothing works. Has anyone made the combined u-boot+power46wl image and can share it?
________
bald ***** Webcam

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

sorry to bump this but I am trying to build a power46wl with u-boot but I constantly fail. Does anybody have it working and can share it?
________
Depakote pregnancy

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

Hey there,
do I have to remove the installed power-kernel-version(v47) and install uboot first?

Thanks for any tips, I really want to test meego, but the uboot-version available through the repositories ist only for version46.

Cheers, Blck

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

Here's a small guide to add u-boot to power48.

1st: Download and install all packages from here

check if it's installed properly with
Is should say 2.6.28.10-power48

Then follow up this little guide ;) (Thx to [DarkGUNMAN] and Fabry's guide of patching power-kernel with u-boot)

Open Terminal:
# Prerequisites
#1. Download power kernel deb file from repository and extract fiasco image from it
#2. Download Matan's u-boot from repository (it is named u-boot-for-power-kernel) and extract file image from it
#3. Unpack Fiasco image
#4. Transform zImage in uImage (necessary because u-boot boots Kernel only in uImage file format)
#5. Add power kernel uImage at end of previous file (starting write at offset 0x38000 aka 448 blocks)
#6. Remove zImage & uImage
#7.1 Flash the kernel
#7.2 Open a new terminal (Shift+Ctrl+X) leave other xterm open!!!
#8. Optional - Multiboot - backup and replace Power48
#9. Optional - Clean Multiboot Entries
If you have old power47 or double power48 entries
open Filebox and navigate to /etc/multiboot.d to delete the respecting *.item files.

#10. Reboot and watch the http://upload.wikimedia.org/wikipedi...-Fresh_tux.png !!! :D

Edit: I coloured the code for whose who don't know what goes together and what not. So, each colored lines are a complete string where to hit 'Enter' after. I left the obvious ones untouched ;)

Greetz,

J4ZZ

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

What are exactly the benefits of power-kernel v47 for you over v46?
If you just want to try meego, why don't you downgrade your power-kernel to v46, go and see what meego has to offer.

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

Everytime I run NITDroid (N12 Gingerbread) it breaks my u-boot.

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

@J4ZZ:
Look, thanks for the guide and all! I know my way around using the command line and even worked with linux for a couple of years. But before using anything like that guide I'd like to have some basic stuff cleared out first.

It's almost unbelievable but I haven't found anywhere anyone that explains what all these boot things are actually doing in detail.

I mean, I was happy to read that if I install kernel power with it's supplied bootimg package, then my guess was that I would be able to multiboot just by doing that. Then I read about this u-boot stuff that I know have been around for a while since the earlier power kernels, that it is obviously needed as well. So what does that provide in comparison with bootimg package? What the hell?

Why do I need the bootimg package, why do I need the u-boot package and why do I need both in order to use multiboot with for instance MeeGo on the SD card.

I know this sounds like like very noob stuff, but I haven't found anywhere here someone explaining the boot process in the N900 and why we need this and that in order to get it to work.
It would be much easier to accept such guides if we understand the reason to what the freaking things are doing that we install.
I have read about the universal bootloader earlier, but not really how it fits into the n900. It's not so strange that some ppl cannot follow simple guides if noone really explains what's going on.

Probably it's explained somewhere, but I sure haven't found it and I'm tired of clicking through +100 pages in threads with unrelated stuff or with guides for dummies that says "do it this way" but not explaining how it is supposed to work in just basic terms.
Where can I read about the darned boot process?

BTW, the search bar here at talk.maemo.org is useless junk.
Rant over.

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

followed instructions (twice) but boot stuck at "Loading kernel..." line.
I've made the procedure with powerk v48.
any thoughts/help?

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

does this work? which instructions did you followed, and were did it exactly fail?

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

Just followed your link instructions (wich seem to be the same has on this thread) and the same happens.
Uboot is stuck on "Starting kernel ..." and the led light is on (strong blue).

PS. I have to remove bat to reflash the non-uboot kernel again

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

yes it's based on this thread and another, as referenced. In one of the thread (this one or the other), it's written that some firmware don't work with the verion of u-boot used here, so maybe it's the case for you :/

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

im in exactly the same situation boots meego fine , But freezes at loading kernel after trying to add u-boot to kernel 48.

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

is there any other working uboot version??

EDIT: Just solved it using uboot in http://wiki.meego.com/ARM/N900/Insta...ge_for_flasher (ubooot.bin from link in point 7)

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

I don't see myself as an expert either regarding those things.
But I would compare it with Windows and Ubuntu for example. Windows has its own bootloader so does Ubuntu and Co...
Windows loads ntldr -> ntdetect.com -> boot.ini and Ubuntu get it's stuff sorted by grub. Booting both systems with just one bootloader doesn't work. Win needs ntldr and Ubuntu needs grub...
So all you can do is to combine these two.
That means you have to have both bootloaders installed and then two possibilities.
First booting Win bootloader and then pointing to grub for starting ubuntu or second booting grub and have it point to ntldr to start windows.

For N900; Meego needs u-boot and multiboot manages maemo, nitdroid and the others. :)
That's it. And because u-boot isn't needed for maemo it's not integrated by default in any kernels.


Sorry for not being able to explain in a more detailed way.

Greetz,

J4ZZ

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

hey J4ZZ - thanks for the quick runthourgh.

Thanks,
Tetris

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

Did this solve the loading issue? ;)

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

I would like to use the newest possible version of u-boot (for booting MeeGo off a different partition on my SD card) while keeping Kernel Power 48 (or Power 49 when it is in repos) How would I go about doing that?

Re: HOWTO: Change, remove or add u-boot on power kernel image
 

*links updated to v48 link!!!!! Lol* :d