Motorola Droid 4 | |
| Manufacturer | Motorola |
|---|---|
| Name | Droid 4 |
| Codename | motorola-maserati |
| Released | 2012 |
| Category | testing |
| Original software | Android 4.1.2 on Linux 3.0 (launched with Android 2.3 on Linux 2.6) |
| Hardware | |
| Chipset | TI OMAP 4430 |
| CPU | Dual-core 1.2 GHz Cortex-A9 |
| GPU | PowerVR SGX540 |
| Display | 540 x 960 TFT |
| Storage | 16 GB |
| Memory | 1 GB |
| Architecture | armhf |
| USB Networking | |
|---|---|
| Flashing | |
| Touchscreen | |
| Display | Works |
| WiFi | |
| Xwayland | |
| FDE | |
| Mainline | |
| Battery | |
| 3D Acceleration | |
| Accelerometer | |
| Audio | |
| Bluetooth | |
| Camera | |
| GPS | |
| Mobile data | |
| SMS | |
| Calls | |
| USB OTG |
Okay, so, I have a Motorola Droid 4 (otherwise known as a Maserati or XT894). The device IS rooted and I have SafeStrap installed. However, during a. The Safestrap screen should show Safestrap Disabled in red, Recovery at the bottom left, and Continue at the bottom right. Tap on Recovery button on the Safestrap main screen to boot into Safestrap recovery mode. Now it’s time to set up a ROM slot for MIUI. To do so, tap on Boot Options and in the very next screen tap on ROM-Slot-1.
Contributors
- TheKit
- Hexarei
- MartijnBraam
Users owning this device
- Eloy (Notes: runs pre-alpha Maemo Leste)
- Foldmorepaper (Notes: kernel v5.1.0)
- Jja2000 (Notes: Running Maemo-Leste)
- Unrznbl (Notes: using instructions I get backlit blank/black screen, will try to make a serial cable)
Rooting
The Droid 4 doesn't have an unlockable bootloader, so rooting the device requires an exploit.
The easiest exploit is called 'Saferoot', which was originally intended for Samsung devices, but also works for many others, including the Droid 4. You can find a saferoot.zip file in this XDA-Developers thread:
Download saferoot.zip, extract it somewhere, then enable USB debugging on the Droid 4 and connect it to your computer. With it connected, open a command line, cd to where you extracted the files, then run install.sh if you're on a Linux machine, or install.bat if you're on a Windows machine.
Following the on-screen instructions, you should eventually have a rooted device!
Custom Recovery: Safestrap
While there's no official version of TWRP for the maserati, there is a custom recovery based on early versions: SafeStrap!
YOU MUST ROOT AS LISTED ABOVE, FIRST!
You can download that here (make sure to get the one with maserati in the name!):
It's an APK file, so enable untrusted sources on your Droid 4 and install it. Once installed, if you're properly rooted, launching it should give you three options: Install recovery, uninstall recovery, and reboot to recovery.
Tapping 'install recovery' should install the SafeStrap recovery! If it's successful, tapping 'Reboot to recovery' should take you to the custom SafeStrap recovery.
Additional Info
Safestrap recovery has support for what it calls 'ROM slots.' At the time of this writing, you must select a non-stock slot in order to flash anything besides Android.
To repeat: DO NOT TRY TO INSTALL pmOS TO THE STOCK SLOT! IT COULD BRICK YOUR DEVICE!.
Installation
Create ROM slot with minimal possible space for system, data, and cache partitions.
First flash CyanogenMod 11 to install files needed by SafeStrap for kexec.
Then connect the phone via USB in SafeStrap and do the following (android-platform-tools need to be installed):
Now you can either flash motorola-maserati.img to sdcard or resize the image on host to desired size and replace userdata.img of ROM slot you created:
Safestrap Rom Slots Emulator
I have a brick! Help! (DANGEROUS)
So you accidentally overwrote the stock slot in SafeStrap. What should you do?
- Use Fastboot to write stock image back. Press the two volume buttons while pressing power to enter the factory bootloader. Find the files in VRZ_XT894_9.8.2O-72_VZW-18-8_CFC.xml.zip and rewrite system.img, boot.img, recovery.img, etc.
- Install kexecboot to mbm partition to avoid SafeStrap altogether and boot from SD card see droid4-kexecboot in the additional information.
Fastboot won't work due to too low a battery
- Charge battery with external LiPo charger - B+ and B- are clearly marked.
- Remove the battery, and insert pins into relevant battery terminals and give appropriate power from lab bench supply. Increasing current past a threshold (but be VERY careful) should fool the bootloader into thinking it has a well-charged battery.
- It may also be possible to charge via the rear 4-pin connector, which goes through the charging circuitry: https://forum.xda-developers.com/showthread.php?t=1887365
- Build a 'factory cable' that bridges ID (micro-USB type-B pin 4) with 5V VCC (pin 1), which is how the factory flashes the devices without any battery at all.
lsmod
Safestrap Rom Slots Game
See also
- #1039 WIP pull request
- KexecBoot for the Droid 4 - quite possibly more desirable than Safestrap
- booting droid 4 xt894 with current kernel - mainlining instructions with Kexecboot for at least 4.20-rc7 kernel (and serial cable how-to)