How to find device specific information

From postmarketOS
Jump to: navigation, search

Android

Generic device information

Fastboot (boot.img) flash offsets

pmbootstrap bootimg_analyze automatizes this and directly gives you what you need to put in the deviceinfo file (more). The information below is only kept for reference, but do yourself a favor and use the automated version instead.

If you can't find a full ROM image for your device, consider extracting the boot.img file directly from your device with adb.

  1. Find the download link for a full image on https://download.lineageos.org/
  2. Run the following commands (replace the download link accordingly)

    pmbootstrap build unpackbootimg
    pmbootstrap chroot
    apk add unpackbootimg
    su - user
    mkdir /tmp/bootimg_info
    cd /tmp/bootimg_info
    wget "https://mirrorbits.lineageos.org/full/hammerhead/20170530/lineage-14.1-20170530-nightly-hammerhead-signed.zip"
    unzip *.zip
    unpackbootimg -i boot.img
  3. Example output:

    Android magic found at: 0
    BOARD_KERNEL_CMDLINE console=ttyHSL0,115200,n8 androidboot.hardware=hammerhead
    user_debug=31 maxcpus=2 msm_watchdog_v2.enable=1
    androidboot.bootdevice=msm_sdcc.1 buildvariant=userdebug
    BOARD_KERNEL_BASE 00008000
    BOARD_RAMDISK_OFFSET 02900000
    BOARD_SECOND_OFFSET 00f00000
    BOARD_TAGS_OFFSET 02700000
    BOARD_PAGE_SIZE 2048
    BOARD_SECOND_SIZE 0
    BOARD_DT_SIZE 0

Translate the variables as follows into your deviceinfo:

  • BOARD_KERNEL_CMDLINE -> deviceinfo_kernel_cmdline
  • BOARD_KERNEL_BASE -> deviceinfo_flash_offset_kernel
  • BOARD_RAMDISK_OFFSET -> deviceinfo_flash_offset_ramdisk
  • BOARD_SECOND_OFFSET -> deviceinfo_flash_offset_second
  • BOARD_TAGS_OFFSET -> deviceinfo_flash_offset_tags
  • BOARD_PAGE_SIZE -> deviceinfo_flash_pagesize
  • BOARD_SECOND_SIZE and BOARD_DT_SIZE can both be ignored
  • (contents of the extracted boot.img-base file) -> deviceinfo_flash_offset_base (defaults to 0x10000000)



NOTE: Some useful info can be pulled via fastboot too (in case you have the device at hand) by executing fastboot getvar all

Kernel version

Device Architecture

  • You can find the architecture while the device is running another kernel (e.g. original Android or TWRP). Run adb shell to gain access to the console on the device, and type uname -m.
  • pmOS supports the armhf and aarch64 architectures. If the output is armv7l, for example, you should use armhf as your device architecture.

Device code name

LineageOS kernel source repository

  • Find out the code name of your device (see above)
  • Usually, you can find the kernel source repository by typing in the code name of your device into the LineageOS GitHub page
  • If you can't find it, but you found a repository starting with android_device_, open that repository and look into the lineage.dependencies file. It lists other LineageOS repositories there - open these repositories, until you finally find the repository with "kernel" in the name. Example: First, Second, Third: Kernel repo!

Other locations for kernel repositories

Kernel defconfig (default config)

  • DEFCONFIG= line inside the build.config inside the kernel repository (if available) (example)
  • Official listing
  • If you found the android_device_ repository (as shown in LineageOS kernel source repository above), look for a TARGET_KERNEL_CONFIG line in the BoardConfig.mk.

In the case where you have located the kernel source for your device but there is no build.config, have a look at the arch/arm/configs/ directory. E.g. for Moto G 2014 "titan" that uses android_kernel_motorola_msm8226 you have a titan_defconfig file there.

Misc info from BoardConfig.mk

Example, contains the following information:

  • kernel commandline
  • ramdisk offset, tags offset, pagesize, base
  • boot partition size

Firmware files

Find the LineageOS repository for your device by using the repository filter function here and typing in your device's code name. You need the repository starting with android_device_. Inside that repository, there should be a proprietary_components.txt or proprietary-files.txt, which has among lots of files, that we do not need, the paths to the firmware files - starting with /vendor/firmware. Combined with some additional research, you should be able to find the files needed for the hardware, that you want to get running (e.g. wifi). Now you have the names of the firmware files. First look if they are provided by linux-firmware, and if not, find them elsewhere and package them yourself (as in samsung-i9070).

See also: Wifi