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.