Re: [HOWTO] Comprehensive Firmware Flashing Guide for Jolla
 

Yes, just like you can perm brick N9 by writing rnd() to CAL partition, if you destroy your bootloader with rnd() values on purpose, then your device is quite a brick (and out of warranty). As even @care uses fastboot to do reflashes, so they wouldn't be able to help you. In case of bricked bootloader, it can only be fixed with non-public factory tools and special factory cable which is only avail in factory-line and few Jolla employees.

So my advice would not mess with bootloader partitions, as those are the only things that you cannot recover from yourself if you happen to accidentally do a mistake. Even I have bricked one device when playing with custom bootloaders (luckily I can recover from accidents)

Re: [HOWTO] Comprehensive Firmware Flashing Guide for Jolla
 

I want that cable ;)

Re: [HOWTO] Comprehensive Firmware Flashing Guide for Jolla
 

Just a preliminary idea:

Make a copy of the 'sailfish' partition:

dd if=/dev/mmcblk0p28 of=/sdcard/sailfish.img

Copy /sdcard/sailfish.img from phone to PC

Connect phone in fastboot mode and flash sailfish.img

fastboot flash sailfish sailfish.img

Would that work ? (will test myself later)

Re: [HOWTO] Comprehensive Firmware Flashing Guide for Jolla
 

I don't know, could work or could permabrick it :)
Is the flashable image format 1:1 bitcopy of the flash content? Might be there are some headers or such prepended to it, in which case it does not work from simple dd'ed image.

Re: [HOWTO] Comprehensive Firmware Flashing Guide for Jolla
 

It is 1:1 I've done it several times with bootimage and recovery. But Systemimage is very big so I think fastboot gets problems

Re: [HOWTO] Comprehensive Firmware Flashing Guide for Jolla
 

Yes, fastboot this way will fail :). I do have imput from Jolla on how this can be solved, but above example is doomed to fail

Re: [HOWTO] Comprehensive Firmware Flashing Guide for Jolla
 

I don't know if it still works, but with some versions of jollas BL you can directly boot your image with fastboot boot imgfile and then recover.

We have been down this road before. The problem above was to recover the device if your bootloader is bricked. Than you need special tools which aren't available

Re: [HOWTO] Comprehensive Firmware Flashing Guide for Jolla
 

If Bootloader is damaged, yes, then it is not possible, you need special tools (I do believe Jolla have those, but thats it).

The fastboot image is usefull in a very rare situation that recovery partition got damaged.

Re: [HOWTO] Comprehensive Firmware Flashing Guide for Jolla
 

Just make sure the device is bootloader unlocked before you do anything critical :D

Re: [HOWTO] Comprehensive Firmware Flashing Guide for Jolla
 

LOL its been that from day 1

Still considering if/how this should/could be implemented in recovery.
What we do need (thank stskeeps) is img2simg tool in order to split up the raw image file in multiple image files of 500M size (due to memory.
I have build this tool for armv7hl so that it may be used on-device
(https://build.merproject.org/project...me:nielnielsen)

stskeeps have also confirmed that the correct name of partition 28 is sailfish as I found out by parted in a previous post in this thread.

Given this information, it actually should be rather trivial to finish this and create a script that could be run, even on device, allowing users to create that rescue image.