[spam] [personal] information on the Unihertz Titan, a mobile phone

Tue Jul 19 04:54:55 PDT 2022

One way to flash and backup this phone is by using the FACTORY
FLASHER. I downloaded SP Flash Tool from
https://androidmtk.com/smart-phone-flash-tool and expanded it to ~/pkg
.

NOTE: New versions of SP Flash Tool will upgrade the boot download
agent (a boot software package with an extensive rpc interface), which
may make it much harder to install 3rd party flashing tools. I have
already performed this mistake on my own device, however.

The flasher uses a scatter file which I believe is just a list of
partition mappings.

The FACTORY IMAGE can be found at
https://drive.google.com/drive/u/0/folders/1fpO65z2_r9zT8UImuV8-5JCRBy33yZcV
. This is in the UnihertzTitan folder on my Windows partition. I do
not recommend using Unihert'z rebranded mediatek flasher, because it
only runs on Windows. The official generic mediatek flashers work fine
and are made for linux, where it is easy to log syscalls etc. There
are b2sums and sha256sums of many of these images in this thread.

The device can also be flashed with FASTBOOT, although this does not
provide for imaging in the other direction. One way to boot to
fastboot is by holding volume-up during boot, then rebooting to
bootloader mode.

First unlock the bootloader:
$ fastboot flashing unlock
And confirm unlocking on the phone by pressing volume-up.

Then flash:
$ fastboot flash system system-quack-arm64-ab-vanilla.img

TREBLE SYSTEM IMAGE b2sums are in the "making my unihertz titan boot"
spam thread at https://lists.cpunks.org/pipermail/cypherpunks/2022-May/099255.html
. The urls for downloading them are like
https://github.com/phhusson/treble_experimentations/releases/download/TAG/system-quack-arm64-ab-vanilla.img.xz
where TAG is something like v207 .

I may have tested these images before, but I haven't quite found where
my work was if so. I recall they stop running after a major change in
the repository.
I have tested these images today:
- v207 runs fine
- v208 runs fine
- v210 runs fine
- v214 runs fine
- v220 runs fine
- v222 runs fine LATEST KNOWN WORKING

URL for the latest image I've booted successfully:
https://github.com/phhusson/treble_experimentations/releases/download/v222/system-quack-arm64-ab-vanilla.img.xz

I have not tested any variants other than "vanilla" at this time.

I got a DIFFERENT CHECKSUM for v208 today. I have only checked the
images listed below. I am assuming that my differing checksum was due
to an incomplete download previously, and including the size here.

b2sum

Differing:
03dc88f81ee58051ffc75ddc8ed5c43c3c73a1dbc598d109b54ad03aaa424b12fb09235da757fa636e97c9fb315752ac5362d72f27c4d5358a66e22814ca1661
 v208-2022-07-19-system-quack-arm64-ab-vanilla.img size=1740550424

New:
055aa5fa084a09e4fed0a5dbb5c8007a29848cf2841dc65b939d0247c246286450172d76951cfef89fa8ae1dcea5d6511fc665219e72a8cfe671b55f5a5d7d60
 v210-2022-07-19-system-quack-arm64-ab-vanilla.img size=1740718336
8131a0411824ffad0ba5d381513820770bdff3b22e412161f4b5c0827027e18b0e040f691f7af2995c98b203049b096646d08463af4fa01b8588e0e172ceea54
v220-2022-07-19-system-quack-arm64-ab-vanilla.img size=1736143104

Same:
aa80d380ac31502dfc548da57414cd6e56ccd12e21be647f82508bec59ae3f36e4d3eee6d3047c73c03075b5d54c15f7bd6bba90a1bf5f73c26bbd33056e3c1e
v207-2022-07-19-system-quack-arm64-ab-vanilla.img size=1740189976
503324691350107f945a1e81c89438eb6d4dde120167eede2d35aee20fb20429949a94da50c457304c009a46ad1ff7d1691158dd19368b1ab44546e8ffea102e
v218-2022-07-19-system-quack-arm64-ab-vanilla.img size=1735053568
486e3ec3184b203bf87b5a2211d33edd07b0667df57660eca42e386e6f6e0201aba49ec0c25fb30fa22dfada6435d9eda618eadfe276bba62f5bde9dfae7a129
 v222-2022-07-19-system-quack-arm64-ab-vanilla.img size=1738010904

BUILDING FROM SOURCE
I haven't done this successfully yet. It likely involves cloning and
building huge trees of android code for a long time.
git clone https://github.com/phhusson/treble_experimentations
cd treble_experimentations
git checkout v222
mkdir build
cd build
# note: this likely builds r40; the v222 releases on github appear to
be r41 . graphene10 is the same android ver as aosp10, could try it
too. the build-dakkar script does more of the repo stuff
automatically.
bash ../build-dakkar.sh aosp10 arm64-ab-vanilla-su
# when it asks to sync, hit Y the first time so as to build the
directory structure I guess

TROUBLESHOOTING PROBLEMS I ran into:
- at first after flashing treble with fastboot, the phone would
BOOTLOOP. I'm wondering if this is because I didn't do `fastboot
flashing unlock` before flashing with fastboot, or maybe because I was
flashing a partial download. I resolved it by reflashing the factory
image and using fastboot again. I did not need to perform OEM
unlocking after resetting to the factory image; it still had OEM
unlocking enabled. I may not have needed to reflash with the factory
image at all.

INCOMPLETE data for accessing the phone directly may be found near
https://github.com/bkerler/mtkclient which is one of the open source
flashers. I also started a python client that does not require root,
at https://github.com/xloem/backyard_mediatek_flasher , before I found
mtkclient. I have not figured out how to use mtkclient yet.