| .. SPDX-License-Identifier: GPL-2.0+ |
| .. sectionauthor:: Dzmitry Sankouski <dsankouski@gmail.com> |
| |
| Snapdragon 845 |
| ================ |
| |
| About this |
| ---------- |
| This document describes the information about Qualcomm Snapdragon 845 |
| supported boards and it's usage steps. |
| |
| SDM845 - hi-end qualcomm chip, introduced in late 2017. |
| Mostly used in flagship phones and tablets of 2018. |
| |
| U-Boot can be used as a replacement for Qualcomm's original ABL (UEFI) bootloader. |
| It is loaded as an Android boot image through ABL |
| |
| Installation |
| ------------ |
| Build |
| ^^^^^ |
| Setup ``CROSS_COMPILE`` for aarch64 and build U-Boot for your board:: |
| |
| $ export CROSS_COMPILE=<aarch64 toolchain prefix> |
| $ make <your board name here, see Boards section>_defconfig |
| $ make |
| |
| This will build ``u-boot.bin`` in the configured output directory. |
| |
| Generate FIT image |
| ^^^^^^^^^^^^^^^^^^ |
| See doc/uImage.FIT for more details |
| |
| Pack android boot image |
| ^^^^^^^^^^^^^^^^^^^^^^^ |
| We'll assemble android boot image with ``u-boot.bin`` instead of linux kernel, |
| and FIT image instead of ``initramfs``. Android bootloader expect gzipped kernel |
| with appended dtb, so let's mimic linux to satisfy stock bootloader: |
| |
| - create dump dtb:: |
| |
| workdir=/tmp/prepare_payload |
| mkdir -p "$workdir" |
| cd "$workdir" |
| mock_dtb="$workdir"/payload_mock.dtb |
| |
| dtc -I dts -O dtb -o "$mock_dtb" << EOF |
| /dts-v1/; |
| / { |
| memory { |
| /* We expect the bootloader to fill in the size */ |
| reg = <0 0 0 0>; |
| }; |
| |
| chosen { }; |
| }; |
| EOF |
| |
| - gzip u-boot ``gzip u-boot.bin`` |
| - append dtb to gzipped u-boot: ``cat u-boot.bin.gz "$mock_dtb" > u-boot.bin.gz-dtb`` |
| |
| Now we've got everything to build android boot image::: |
| |
| mkbootimg --base 0x0 --kernel_offset 0x00008000 \ |
| --ramdisk_offset 0x02000000 --tags_offset 0x01e00000 \ |
| --pagesize 4096 --second_offset 0x00f00000 \ |
| --ramdisk "$fit_image" \ |
| --kernel u-boot.bin.gz-dtb \ |
| -o boot.img |
| |
| Flash image with your phone's flashing method. |
| |
| Boards |
| ------------ |
| starqlte |
| ^^^^^^^^^^^^ |
| |
| The starqltechn is a production board for Samsung S9 (SM-G9600) phone, |
| based on the Qualcomm SDM845 SoC. |
| |
| More information can be found on the `Samsung S9 page`_. |
| |
| .. _Samsung S9 page: https://en.wikipedia.org/wiki/Samsung_Galaxy_S9 |