Samsung Exynos 7 (samsung-exynos7)

U-Boot
Primary Bootloader Whether it is possible to replace stock bootloader with U-Boot.	Broken
Secondary Bootloader Whether it is possible to chainload U-Boot from stock bootloader.	Works
Mainline Whether latest upstream versions of U-Boot are not broken and it is possible to use them.	Works
Internal Storage Whether it is possible to boot from internal storage (e.g. eMMC or UFS).	Works
SD card Whether it is possible to boot from SD card.	Works
USB Host Whether it is possible to boot from a USB storage or connect a keyboard.	Broken
USB Peripheral Whether it is possible to use device as a peripheral in U-Boot, e.g. for fastboot mode.	Works
Display	Works
Buttons Whether it is possible to navigate in boot menu or grub with volume and power buttons.	Works

Features
Flashing Whether it is possible to flash the device with pmbootstrap flasher.	Works
USB Networking After connecting the device with USB to your PC, you can connect to it via telnet (initramfs) or SSH (booted system).	Works
Internal storage eMMC, SD cards, UFS...	Works
SD card Also includes other external storage cards.	Works
Battery Whether charging and battery level reporting work.	Broken
Screen Whether the display works; ideally with sleep mode and brightness control.	Works
Touchscreen	Works
Multimedia
3D Acceleration	Works
Audio Audio playback, microphone, headset and buttons.	Broken
Camera	Broken
Camera Flash	Broken
Connectivity
WiFi	Broken
Bluetooth	Broken
GPS	Broken
Modem
Calls	Broken
SMS	Broken
Mobile data	Broken
Miscellaneous
FDE Full disk encryption and unlocking with unl0kr.	Works
USB OTG USB On-The-Go or USB-C Role switching.	Broken
Sensors
Accelerometer Handles automatic screen rotation in many interfaces.	Works
Ambient Light Measures the light level; used for automatic screen dimming in many interfaces.	Works
Proximity	Works
Hall Effect Measures magnetic fields; usually used as a flip cover sensor	Broken
Haptics	Works

Samsung Exynos 7
	; samsung-on7xelte, an Exynos 7 device, running Phosh
Manufacturer	Samsung
Name	Exynos 7
Codename	samsung-exynos7
Type	generic
Hardware
Chipset	Samsung Exynos 7
Architecture	aarch64
Software
Original software The software and version the device was shipped with.	Android
Extended version The most recent supported version from the manufacturer.	Android
FOSS bootloader	partial
postmarketOS
Category	testing
Pre-built images Whether pre-built images are available from the postmarketOS Installation page.	no
Mainline Instead of a Linux kernel fork, it is possible to run (Close to) Mainline.	yes
Device package	device-samsung-exynos7
Kernel package	linux-postmarketos-stable; linux-postmarketos-lts; linux-postmarketos-mainline; linux-postmarketos-exynos7870

This device is based on the Exynos 7 family of SoCs.
See the SoC page for common tips, guides and troubleshooting steps

This is a generic port that boots with UEFI for Samsung Exynos 7 based devices.

Device	Codename	Chipset	Architecture
Samsung Galaxy A2 Core	samsung-a2corelte	Samsung Exynos 7870 Octa	aarch64
Samsung Galaxy J6 (2018)	samsung-j6lte	Samsung Exynos 7870 Octa	aarch64
Samsung Galaxy J7 (2016)	samsung-j7xelte	Samsung Exynos 7870 Octa	aarch64
Samsung Galaxy J7 Prime	samsung-on7xelte	Samsung Exynos 7870 Octa	aarch64

Contributors

Bluebunny (Contributor)
Naproxen (Maintainer)

How to enter flash mode

Download (Heimdall): See the wiki page for your device. Key combinations to enter Samsung's Download mode differ between devices.
Fastboot (U-Boot): Power on the device by holding down Volume Down until you see the U-Boot Boot Menu. Select Enter Fastboot Mode.

Prerequisites

Although on some devices the bootloader doesnt need a unlock, but if it needs make sure your phone’s bootloader is unlocked. You can do this by enabling OEM unlocking in the Developer Options menu of the stock Android Settings app.

Installation

U-Boot (UEFI boot loader)

Exynos 7 devices have S-Boot or S-LK as the default boot loader. These Samsung bootloaders are known to be very weird. There have been reports for having no boot splash screen or having less RAM than normal when booted with the stock bootloader. Even worse, they can't boot with EFI and overwrite any OS-provided cmdline.

For this reason, a secondary boot loader must be used. Das U-Boot is a popular boot loader which supports a subset of the UEFI specification. It can be installed to the Android boot partition as a secondary boot loader, providing a clean environment for booting mainline Linux. Additionally, it also provides the standard fastboot interface.

Pre-builts

Tauchgang U-Boot provides community releases for Linux Mobile devices and development boards. Along with pre-built images, they also push to LVFS, which means you can easily update Tauchgang itself with fwupd. All devices currently supported by samsung-exynos7 can use Tauchgang.

Visit https://gitlab.postmarketos.org/tauchgang/u-boot/-/artifacts.
Find your device. (e.g. build-samsung-on7xelte)
Check if the build is release. If the branch name doesn't start with release/, click the Next > button below until you find one.
Download artifacts.zip and unzip it.
Reboot the phone into Download mode.
Flash the u-boot-*.img to BOOT using Heimdall:

$ heimdall flash --BOOT u-boot-vendor-codename.img

Your phone will reboot and you will be greeted with an U-Boot screen.

Manual build

Use Tauchgang if possible, manually built U-Boots don't get updated automatically.

If you want to manually build U-Boot for debugging, follow the guides below:

postmarketOS

WARNING: Never use pmbootstrap flasher flash_kernel, even if pmbootstrap suggests you to do so. It will overwrite U-Boot and make the device unbootable.

Pre-built images are not available at the moment. Follow the installation guide with pmbootstrap. Below are the examples for building your own image.

If you don't like having full-disk encryption, omit --fde.

If you have installed the OS to both the internal storage and the SD card, the SD card one will be booted.

Install to internal storage

$ pmbootstrap init
$ pmbootstrap install --fde

Enter fastboot mode inside U-Boot (NOT Samsung's Download mode) and flash the rootfs:

$ pmbootstrap flasher flash_rootfs

Reboot the device, and it will boot into postmarketOS.

Install to an SD card

Internal storage can be tiny for heavy interfaces, such as Phosh or Plasma Mobile. Some devices can't be flashed internally because U-Boot's fastboot doesn't detect the internal emmc. In such cases, you can install to an SD card instead.

$ pmbootstrap init
$ pmbootstrap install --fde --disk=/path/to/sdcard

Plug the SD card inside the device and reboot. It will boot into postmarketOS.

Known Issues

Generic kernels

Wi-Fi: doesn't work.

Close-to-mainline kernel

Charging: No battery charger driver exists, which is responsible for reporting charge status and control.
Brightness: Display works with simple framebuffer, so you can't control the panel brightness.
USB Gadget: The host may not receive network packets from the device, unless the host sends packets to the device. Due to this behavior, SSH (among other things) doesn't work well. A workaround is to have ping -Aq <IP> run in the background while you interact with the device (replace <IP> with the device IP address).

Problems

Wi-Fi

Wi-Fi behaves very erratically (practically unusable) when the SDIO is probed in DMA mode. The driver fails to communicate with the SDIO, reporting timeout errors. The PIO transfers happen to be stable though.

Some devices don't support 5 GHz or WPA3. If the 2.4 GHz encryption is set to WPA3-only or WPA2/WPA3 transition mode, it will refuse to connect and repeatedly prompt you for a new password, even if the correct one is entered. To fix this, set the encryption to WPA2-PSK only in your router's configuration menu.