Fastboot flashing of Jolla C2

jovirkku · 19 December 2024 09:12

Fastboot flashing of a Jolla C2

1. Download the latest Sailfish OS release for C2

Sign in to Jolla Shop with your Jolla username.
Get the “Free Trial for supported devices” licence.
Download the C2 zip file from the Downloads.
Unzip the C2 zip file to your Linux computer. The following files (with approximately similar sizes) should appear:

2. Update the bootloader

If you have already updated your C2 to OS version 5.0.0.43 (or later), go to Chapter 3. The bootloader of your C2 is up to date.

The bootloader of some OS releases (5.0.0.29 or earlier) must be updated to allow fastboot flashing.

Copy the lk.bin from the C2 zip file to your C2 device (MTP/USB) and check that the md5sum matches.

[defaultuser@JollaC2 ~]$ md5sum lk.bin 
20c0b9996de86994cebf55b9eaf74d15  lk.bin

Working as root on the C2 phone, copy the lk.bin to /boot/ and run the flash-bootloader script.

[defaultuser@JollaC2 ~]$ devel-su 
Password: 
[root@JollaC2 defaultuser]# cp lk.bin /boot/lk.bin
[root@JollaC2 defaultuser]# /var/lib/platform-updates/flash-bootloader.sh

Turn the phone off.

3. Install Sailfish OS with fastboot

NOTE: Flashing will delete all of your data on the phone. Copy valuable data to a safe storage outside of the phone.

When the C2 phone is off, press the Power key until you feel the vibrator play shortly. Release the Power key. Press and hold the Volume Down key. The phone should vibrate again.

Check that the tiny “fastboot mode” text appears at the top left corner of the screen while the C2 and Sailfish OS logos appear in the middle (click on the “Picture” below).

Picture

Connect the phone with a USB cable to your Linux computer (*). Open a terminal on the computer to the folder where you unzipped the C2 zip file.

Give the following command in the terminal to check that the fastboot mode is okay. Your C2 should respond with a one-liner as below (with a different number, though).

$ sudo fastboot devices
21210112221590	 fastboot Data

If the command above failed (did not print anything)

If the previous command failed (did not print anything) you should install the fastboot tool on your computer.

Debian/Ubuntu/.deb distributions:

sudo apt-get install android-tools-fastboot

Fedora:

dnf install android-tools

OpenSUSE:

zypper install android-tools

Now, try again:

 sudo fastboot devices

FLASHING TO START

Give the following commands one by one (‘sudo’ may not be necessary). We recommend copy-pasting the commands to avoid typos.

sudo fastboot flash boot_a hybris-boot.img
sudo fastboot flash boot_b hybris-boot.img
sudo fastboot flash vendor_boot_a vendor_boot.img
sudo fastboot flash vendor_boot_b vendor_boot.img
sudo fastboot flash dtbo_a dtbo.img
sudo fastboot flash dtbo_b dtbo.img
sudo fastboot flash userdata sailfish.img001
sudo fastboot flash super fimage.img001

The last two commands may take up to 3-4 minutes in total.

(*) Fastboot flashing also works on Windows computers with the Sony fastboot driver installed for Xperia phones! Install the driver in this way. You will need an Xperia phone to do it. You will also need to copy the two DLL files and fastboot.exe from an Xperia flashing folder to the C2 folder.

Command line view

Flashing output

$ sudo fastboot flash boot_a hybris-boot.img
[sudo] password for <username>: 
Sending 'boot_a' (46560 KB)                        OKAY [  1.572s]
Writing 'boot_a'                                   OKAY [  0.280s]
Finished. Total time: 1.906s

$ sudo fastboot flash boot_b hybris-boot.img
Sending 'boot_b' (46560 KB)                        OKAY [  1.552s]
Writing 'boot_b'                                   OKAY [  0.253s]
Finished. Total time: 1.853s

$ sudo fastboot flash vendor_boot_a vendor_boot.img
Sending 'vendor_boot_a' (102400 KB)                OKAY [  3.471s]
Writing 'vendor_boot_a'                            OKAY [  0.603s]
Finished. Total time: 4.196s

$ sudo fastboot flash vendor_boot_b vendor_boot.img
Sending 'vendor_boot_b' (102400 KB)                OKAY [  3.266s]
Writing 'vendor_boot_b'                            OKAY [  0.564s]
Finished. Total time: 3.888s

$ sudo fastboot flash dtbo_a dtbo.img
Sending 'dtbo_a' (8192 KB)                         OKAY [  0.296s]
Writing 'dtbo_a'                                   OKAY [  0.151s]
Finished. Total time: 0.472s

$ sudo fastboot flash dtbo_b dtbo.img
Sending 'dtbo_b' (8192 KB)                         OKAY [  0.300s]
Writing 'dtbo_b'                                   OKAY [  0.142s]
Finished. Total time: 0.455s

$ sudo fastboot flash userdata sailfish.img001
Sending sparse 'userdata' 1/22 (131032 KB)         OKAY [  4.788s]
Writing 'userdata'                                 OKAY [  0.018s]
Sending sparse 'userdata' 2/22 (128199 KB)         OKAY [  5.456s]
Writing 'userdata'                                 OKAY [  0.011s]
Sending sparse 'userdata' 3/22 (120957 KB)         OKAY [  4.042s]
Writing 'userdata'                                 OKAY [  0.001s]
Sending sparse 'userdata' 4/22 (130851 KB)         OKAY [  4.680s]
Writing 'userdata'                                 OKAY [  0.006s]
Sending sparse 'userdata' 5/22 (129105 KB)         OKAY [  4.539s]
Writing 'userdata'                                 OKAY [  0.004s]
Sending sparse 'userdata' 6/22 (131070 KB)         OKAY [  5.102s]
Writing 'userdata'                                 OKAY [  0.004s]
Sending sparse 'userdata' 7/22 (131068 KB)         OKAY [  4.891s]
Writing 'userdata'                                 OKAY [  0.001s]
Sending sparse 'userdata' 8/22 (131068 KB)         OKAY [  4.675s]
Writing 'userdata'                                 OKAY [  0.001s]
Sending sparse 'userdata' 9/22 (117133 KB)         OKAY [  4.201s]
Writing 'userdata'                                 OKAY [  0.001s]
Sending sparse 'userdata' 10/22 (121840 KB)        OKAY [  4.411s]
Writing 'userdata'                                 OKAY [  0.008s]
Sending sparse 'userdata' 11/22 (130882 KB)        OKAY [  4.937s]
Writing 'userdata'                                 OKAY [  0.005s]
Sending sparse 'userdata' 12/22 (130980 KB)        OKAY [  5.138s]
Writing 'userdata'                                 OKAY [  0.008s]
Sending sparse 'userdata' 13/22 (131069 KB)        OKAY [  5.009s]
Writing 'userdata'                                 OKAY [  0.005s]
Sending sparse 'userdata' 14/22 (127027 KB)        OKAY [  4.614s]
Writing 'userdata'                                 OKAY [  0.006s]
Sending sparse 'userdata' 15/22 (131068 KB)        OKAY [  4.583s]
Writing 'userdata'                                 OKAY [  0.013s]
Sending sparse 'userdata' 16/22 (127993 KB)        OKAY [  4.449s]
Writing 'userdata'                                 OKAY [  0.006s]
Sending sparse 'userdata' 17/22 (117585 KB)        OKAY [  4.388s]
Writing 'userdata'                                 OKAY [  0.003s]
Sending sparse 'userdata' 18/22 (121588 KB)        OKAY [  4.508s]
Writing 'userdata'                                 OKAY [  0.001s]
Sending sparse 'userdata' 19/22 (129141 KB)        OKAY [  4.808s]
Writing 'userdata'                                 OKAY [  0.010s]
Sending sparse 'userdata' 20/22 (131021 KB)        OKAY [  4.648s]
Writing 'userdata'                                 OKAY [  0.001s]
Sending sparse 'userdata' 21/22 (130974 KB)        OKAY [  4.843s]
Writing 'userdata'                                 OKAY [  0.014s]
Sending sparse 'userdata' 22/22 (79404 KB)         OKAY [  2.785s]
Writing 'userdata'                                 OKAY [  0.013s]
Finished. Total time: 102.144s

$ sudo fastboot flash super fimage.img001
Sending sparse 'super' 1/11 (131068 KB)            OKAY [  5.018s]
Writing 'super'                                    OKAY [  0.008s]
Sending sparse 'super' 2/11 (131068 KB)            OKAY [  4.990s]
Writing 'super'                                    OKAY [  0.000s]
Sending sparse 'super' 3/11 (131068 KB)            OKAY [  4.852s]
Writing 'super'                                    OKAY [  0.004s]
Sending sparse 'super' 4/11 (131068 KB)            OKAY [  4.700s]
Writing 'super'                                    OKAY [  0.004s]
Sending sparse 'super' 5/11 (131068 KB)            OKAY [  4.859s]
Writing 'super'                                    OKAY [  0.004s]
Sending sparse 'super' 6/11 (131068 KB)            OKAY [  4.626s]
Writing 'super'                                    OKAY [  0.000s]
Sending sparse 'super' 7/11 (131068 KB)            OKAY [  4.908s]
Writing 'super'                                    OKAY [  0.005s]
Sending sparse 'super' 8/11 (131068 KB)            OKAY [  4.827s]
Writing 'super'                                    OKAY [  0.000s]
Sending sparse 'super' 9/11 (131068 KB)            OKAY [  4.959s]
Writing 'super'                                    OKAY [  0.006s]
Sending sparse 'super' 10/11 (131068 KB)           OKAY [  4.761s]
Writing 'super'                                    OKAY [  0.000s]
Sending sparse 'super' 11/11 (109792 KB)           OKAY [  3.978s]
Writing 'super'                                    OKAY [  0.006s]
Finished. Total time: 52.539s

Once done, give the command

fastboot reboot

and detach the USB cable.

The phone boots up to the Sailfish OS.

mettska · 19 December 2024 09:49

What has to be done to increase the space on /root while flashing?

jovirkku · 19 December 2024 10:13

Just run the flashing commands.

jenry · 19 December 2024 19:37

Just flashed mine. First had to figure out how to get windows to recognize fastbooting phone.device manager showed yellow triangle and I had to download fastboot driver. Then i just copied those lines when i was in correct folder and now root partition is bigger.

I haven´t rooted any phones in 10 years and dont own coding skills but got the job done.

Bohdan · 20 December 2024 14:50

Does C2 has some kind of an activation lock? Say, what will happen if a user forgets password and then reflashes the device?

Ride92 · 20 December 2024 15:51

Should there be some drivers installed?

I have this problem on windows 10. I did what instruction said and still:

My Jolla C2 says it is in fastboot mode on left top corner but in windows it appears like this:

What should I do?

jenry · 20 December 2024 16:00

Yes i had to download and install fastboot driver for windows.

Ride92 · 20 December 2024 16:09

Can U link to exact drivers you used?

jenry · 20 December 2024 17:58

Yes it was that one. [GitHub - fawazahmed0/Latest-adb-fastboot-installer-for-windows: A Simple Android Driver installer tool for windows (Always installs the latest version)]

harbourlights · 20 December 2024 19:52

Flashed mine with a Linux computer and everything went fine - thank you for the instructions!

olf · 21 December 2024 01:36

@jovirkku, this is a great step forward!

But AFAICS there is no recovery.img provided yet: Is Jolla going to provide one for their C2 phone in the future?

pschlander · 21 December 2024 10:48

Flashed my C2 with my Linux computer, just to get the enlarged root partition size (10 GB).
Everything worked just fine.

Marvmarv89 · 22 December 2024 14:47

This might be a stupid question, but I’m fairly new to Sailfish OS. Do I specifically require a Linux PC or is this flashing procedure also possible with a Mac computer via the Terminal? I have a MacBook Pro with M3 Max Chip and the latest operating system macOS Sequoia 15.2.

aspergerguy · 22 December 2024 15:20

Guessing that you would need Homebrew and Android Platform Tools installed?
https://www.igeeksblog.com/how-to-install-homebrew-on-mac/

Marvmarv89 · 22 December 2024 16:57

Thank you so much aspergerguy, with your help I was able to flash my Jolla C2 on my Mac I can’t thank you enough

I have installed Homebrew as per your link and then entered the following into the Terminal followed by the return key to install Android Platform Tools:

brew install --cask android-platform-tools

Once the installation of Android Platform Tools has been completed, I have closed the active Terminal window. I have then downloaded the C2 release image as per the repository link in step 1 of this thread.
Then, I have navigated to the unzipped folder in the Finder (it was in my downloads folder). While holding down the CTRL key, I have left-clicked the folder, then selected “New Terminal at Folder” from the menu. This has opened a new Terminal window with that folder.
I then connected my Jolla C2 with a USB-C cable to my Mac and followed the instructions outlined in step 3 of this guide to prepare the phone (rebooting and getting into the fastboot mode).

Finally, I have simply copied and pasted one by one the commands from step 3 of the guide in this thread each followed by hitting the return key. When prompted to enter the password, enter the Mac user password and hit return.

After the reboot command, the Jolla C2 rebooted and was reset accordingly. Everything worked as expected =) Thanks also to jovirkku for the guide

aspergerguy · 22 December 2024 18:01

@Marvmarv89
Thanks for confirmation as I had been trying to avoid moving on from Intel Macs since flashing a variety of Nokia/Sailfish devices over the last 10 years.

Marvmarv89 · 22 December 2024 18:17

I can only recommend doing the switch to the Apple silicon based Macs, I have been using them since the M1 chip and I have not run into any issues. And the M3 Max chip in my MacBook Pro is so powerful that I can even play games like Baldur’s Gate 3 on highest settings. Sorry for getting a bit off-topic.

Anyway I am glad I could confirm that flashing the C2 with an ARM based Mac is indeed possible and thanks again for the help provided.

explit · 23 December 2024 12:00

Probably not. But as i know SailfishOS has some packages for device management. Only when the device is registered in this device management app - than it can be remotely locked, deleted etc…

Btw. I am also from Kyiv. But long time ago…

b0necrusher · 4 January 2025 20:20

Thanks, everything worked for me on Fedora 41. Except the reboot command, but that’s not important luckily.

wosrediinanatour · 5 March 2025 22:45

@jovirkku Is there somewhere a hybris-recovery.img?
(I also don’t have any download at shop.jolla.com for C2 )