I installed `u-boot-flasher` and flashed it. I completely forgot that I need a separate package for the power kernel, `kernel-power-bootimg`.

I'm on CSSU Thumb, so the booting attached stock kernel fails. I flashed the power53 kernel by

Is there any way to fix this without a full reflash?

Do you have /lib/modules/2.6.28.10-power53 ? If no then unpack kp53 deb and copy them.

Well, I can't access the rootfs (the MeeGo rescue initrd doesn't expose it) and after flashing power53 (and even u-boot back later on) the device doesn't go past the white screen with Nokia logo.

Why meego rescue? In rescueOs there are ready scripts to mount rootfs and IIRC you can even chroot to it. I would also recommend to fsck opt after your failed boots.

I have /lib/modules/2.6.28.10-power53. /lib/modules/current points to this directory too.

fsck'ed my opt, no success

So I have no idea. I did this procedure with success in my old n900 when I had for example broken vfat partition so u-boot couldn't load image. Maybe there is more thing you did and this affect system.

Is there any way to get some boot log?

modprobe fbcon to /sbin/preinit

I don't even reach the output which should be printed after adding modprobe fbcon.

It's so borked that I ended up flashing.