Ubuntu Touch Porting for Samsung Galaxy A11q on Fedora

Introduction

This guide provides step-by-step instructions to set up a development environment on Fedora for porting Ubuntu Touch to the Samsung Galaxy A11q. We will cover everything from setting up the necessary tools and libraries to unpacking the stock firmware and extracting critical kernel and boot image details.

Environment Setup

1. Install Repo Tool

The repo tool is used for managing Android source code. Install it using the following command:

sudo dnf install repo

2. Update Your PATH

Add the ~/bin directory to your PATH environment variable:

mkdir -p ~/bin
echo 'export PATH=$PATH:$HOME/bin' >> ~/.bashrc
source ~/.bashrc

3. Install Development Tools

Install a set of development tools required for building Android kernels:

sudo dnf groupinstall "Development Tools"

4. Install 32-bit Library Support

Ensure 32-bit libraries are installed for cross-compilation purposes:

sudo dnf install gcc-c++ glibc-devel.i686 libstdc++-devel.i686

5. Install Required Dependencies

The following packages are needed for building the kernel and managing related tasks:

sudo dnf install gcc make glibc-devel bc bison \
ca-certificates cpio curl flex git kmod openssl-devel ncurses-compat-libs python3 \
unzip wget xz jq

6. Install XML Utilities

To handle XML files, you need libxml2:

sudo dnf install libxml2

7. Clone and Compile the img2simg Tool

The img2simg tool is necessary to convert Android sparse images to standard image formats. Follow these steps:

git clone https://coral.googlesource.com/img2simg
cd img2simg/libsparse
gcc -I. -Iinclude -o img2simg img2simg.c sparse_crc32.c sparse_err.c sparse_read.c sparse.c backed_block.c output_file.c -lz

8. Move img2simg to System Path

Move the compiled binary to the /usr/local/bin directory for global access:

sudo mv img2simg /usr/local/bin/

Kernel Source

For the clean kernel source with Halium patches, please visit our GitLab repository.

This repository focuses on the Ubuntu Touch porting process for the Samsung Galaxy A11q.

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Working with Stock Firmware

Extracting boot.img and dtbo.img

1. Download Stock Firmware: Download the appropriate stock firmware for your device (Samsung Galaxy A11). Tools like Frija or websites like SamMobile can help you obtain official firmware files.

2. Extract the .tar.md5 Firmware: Once downloaded, untar the .tar.md5 file to access the various partitions:

   tar -xvf firmware.tar.md5 -C ~/temp

   After extraction, you'll see .img files such as boot.img.lz4, dtbo.img.lz4, and vendor_boot.img.lz4.

3. Decompress .lz4 Files: Use the lz4 tool to decompress the boot.img and dtbo.img files:

   lz4 -d boot.img.lz4 boot.img
   lz4 -d dtbo.img.lz4 dtbo.img

4. Unpack boot.img: After decompression, use the unpack_bootimg.py script to extract kernel offsets and other essential data:

   python3 unpack_bootimg.py --boot_img boot.img --out out

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Filling in Device Information

After unpacking the boot.img, extract key values and fill them in your deviceinfo file:

• Page Size: deviceinfo_flash_pagesize="2048"
• Kernel Load Address: deviceinfo_flash_offset_kernel="0x80008000"
• Ramdisk Load Address: deviceinfo_flash_offset_ramdisk="0x82000000"
• Second Bootloader Load Address: deviceinfo_flash_offset_second="0x00000000" (if applicable)
• Kernel Tags Load Address: deviceinfo_flash_offset_tags="0x81e00000"
• DTB Address: deviceinfo_flash_offset_dtb="0x81f00000"
• OS Version: deviceinfo_bootimg_os_version="12.0.0"
• OS Patch Level: deviceinfo_bootimg_os_patch_level="2023-11"
• Command Line Args:

  deviceinfo_kernel_cmdline="console=ttyMSM0,115200,n8 androidboot.console=ttyMSM0 androidboot.hardware=qcom user_debug=30 msm_rtb.filter=0x237 ehci-hcd.park=3 androidboot.bootdevice=7824900.sdhci lpm_levels.sleep_disabled=1 earlycon=msm_hsl_uart,0x78af000 androidboot.usbconfigfs=true vmalloc=300M loop.max_part=7"