Turn your Kobo into a Debian Linux tablet

[MarekGibek]

HI mmax,

I'm not sure if you can use my image on Kobo Mini, but if that's what Mr_Ploppy did probably you can...

I had similar problems with booting from my SD-cards. Try formatting it with SD-Formatter first (it fixed my SD card):
https://www.sdcard.org/downloads/formatter_4/
Enable "Format Size Adjustment" option!

Then write an image to it.

If this won't work - there is another workaround you can override kernel only on working card and copy needed files manually.

[MarekGibek]

Originally Posted by mmax

Hi,

BTW: The Idea is to connect a GPS module to the serial port of the kobo (Which I allready did successfully with using the xcsoar software for paragliding) and run navit [1] on the device to use as a bicycle computer for my trip next week. I basically only need a moving map application which showes the planned track I want to ride.

[1] http://wiki.navit-project.org

Really cool!!! Good luck! I see no reason why it wouldn't work.

[mmax]

No, same problem.

Are there any arguments I should use like block-size when dumping the image on the sd card?

[mmax]

That's how my SD card looks like with gparted after applying markes image ... Maybe it's the 9MB empty space at the beginning?

[WS64]

The 9MB at the begining is an indicator for primary partition or not. I ran into that problem too with the original Kobo firmware. Not sure which is needed, change it, either to primary (if it is not set) or remove the primary (if it is set) and try again.

btw, I ran Debian on my Mini, it worked. But I just checked it out when this thread was new and did not use it after a few days.

[embryo]

Originally Posted by mmax

That's how my SD card looks like with gparted after applying markes image ... Maybe it's the 9MB empty space at the beginning?

No. This 'empty' space has code necessary to boot. (At least, thats the case for the Android and, I think, the Kobo images)
You should be very careful not to touch it.

[Aydan]

This unallocated space holds the partition table, the u-boot loader, the u-boot environment variables, the kernel and the e-ink waveform data.
Most ARM devices do it like that.

Regards
Aydan

EDIT: forgot the HW-config block, it sits in there as well.

[mmax]

Ok, makes sense ... but why doesn't my Kobo mini boot into debian?
Can anyone else who has a working Kobo mini with debian, supply me with his sd-card image.

I really want to use it as a bike-computer, as described above, but my trip will start on friday (in three days) and time is running out.

Thanks,
Max

[Aydan]

What you should probably do is copy the first couple of megabytes of unpartitioned space from an original kobo mini card/image and then put mareks kernel back in. This way you get all the e-ink data and the hardware config block as well.

Regards
Aydan

[mmax]

Allright, here is the partition from a working kobo image:

fdisk /dev/sdd

Command (m for help): p

Disk /dev/sdd: 1977 MB, 1977614336 bytes
61 heads, 62 sectors/track, 1021 cylinders, total 3862528 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sdd1           19456      543744      262144+  83  Linux
/dev/sdd2          543745     1068033      262144+  83  Linux
/dev/sdd3         1068034     3829762     1380864+   b  W95 FAT32

So I have to get the first 19455 sectors (I guess these are the sectors) with a sector-size of 512 bytes, as printed from fdisk. So I'll try:

dd if=/dev/sdd of=boot_sector_kobo.img seek=0 bs=512 count=19455
19455+0 records in
19455+0 records out
9960960 bytes (10 MB) copied, 0,664918 s, 15,0 MB/s

Allright 'ls -h' gives me a size of 9.5MB of the image ... so I'll give it a try

[Aydan]

you'll have to skip the first sector or you'll overwrite the partition table.
so use skip=1 seek=1 when writing the image to the other card.
also check if the other card has enough space before the first partiton or you'll kill the filesystem there.

[mmax]

Yep ... that's exactly what happened ;-)

[Aydan]

Here's some more info on what is where:
serial number/revision is at block 1
Uboot starts at block 2 (length ??)
HW CONFIG is at block 1024 (length 1)
Kernel is at block 2048 (length ??)
Waveform is at block 14335 (length 2)

[mmax]

I still couldn't fix it ... it would be more easy if someone would supply me with a working kobo mini image, but no one is responding to private messages :-(

Allrigt, so keep on trying. What I tried now was:

dd if=boot_sector_kobo.img of=/dev/sdd seek=2 bs=512 count=19453
19453+0 records in
19453+0 records out
9959936 bytes (10 MB) copied, 0,144711 s, 68,8 MB/s

where boot_sector_kobo.img is the dump of the first 9.5MB, which is the 'free' space at the beginning. But still it doesn't work. I'm not sure if the arguments "seek=2 bs=512" really skip the first 1024 bytes at the destination ... according to the man-page of dd there is also the 'skip' option, but I'm not really sure what to use

According to this post, you have to replace the following parts of markes image to run it on the kobo mini:

u-boot:    bytes 1025 - 71168 ( from sector 2, length 137 sectors )
hw-config: bytes 524288 - 525312 (from sector 1024, length 1 sector )

Thanks,
Max

[Aydan]

dd if=boot_sector_kobo.img of=/dev/sdd seek=2 bs=512 count=19453

this should be

dd if=boot_sector_kobo.img of=/dev/sdd seek=2 skip=2 bs=512 count=19453

What you did is to start writing your whole image from sector 2, so everything is off by 2 sectors.
What i would suggest you do is dd mareks image onto your SD-card, extract the serial, hwinfo and waveform data from the original sd-card with

dd if=/dev/sdd of=serial bs=512 skip=1 count 1
dd if=/dev/sdd of=hwinfo bs=512 skip=1024 count 1
dd if=/dev/sdd of=waveform bs=512 skip=14335 count 2

and copy those files onto the new sdcard with

dd if=serial of=/dev/sdd bs=512 seek=1
dd if=hwinfo of=/dev/sdd bs=512 seek=1024
dd if=waveform of=/dev/sdd bs=512 seek=14335

Regards
Aydan

PS: seek means go to position in output, skip means goto position in input