blob: 3d08b88c39be3c672525b5b5e7e176f12589f05a [file] [log] [blame]
.. SPDX-License-Identifier: GPL-2.0+
.. sectionauthor:: Dzmitry Sankouski <dsankouski@gmail.com>
Qualcomm generic boards
=======================
About this
----------
This document describes how to build and run U-Boot for Qualcomm generic
boards. Right now the generic target supports the Snapdragon 845 SoC, however
it's expected to support more SoCs going forward.
SDM845 - hi-end qualcomm chip, introduced in late 2017.
Mostly used in flagship phones and tablets of 2018.
The current boot flow support loading u-boot as an Android boot image via
Qualcomm's UEFI-based ABL (Android) Bootloader. The DTB used by U-Boot will
be appended to the U-Boot image the same way as when booting Linux. U-Boot
will then retrieve the DTB during init. This way the memory layout and KASLR
offset will be populated by 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-nodtb.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-nodtb.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.
Boards
------
starqlte
^^^^^^^^
The starqltechn is a production board for Samsung S9 (SM-G9600) phone,
based on the Qualcomm SDM845 SoC.
This device is supported by the common qcom_defconfig.
The DTB is called "starqltechn.dtb"
More information can be found on the `Samsung S9 page`_.
dragonboard845c
^^^^^^^^^^^^^^^
The dragonboard845c is a Qualcomm Robotics RB3 Development Platform, based on
the Qualcomm SDM845 SoC.
This device is supported by the common qcom_defconfig
The DTB is called "dragonboard845c.dtb"
More information can be found on the `DragonBoard 845c page`_.
qcs404-evb
^^^^^^^^^^
The QCS404 EvB is a Qualcomm Development Platform, based on the Qualcomm QCS404 SoC.
This device is supported by the common qcom_defconfig
The DTB is called "qcs404-evb.dtb"
Building steps
--------------
Steps:
- Build u-boot::
$ export CROSS_COMPILE=<aarch64 toolchain prefix>
$ make qcom_defconfig
$ make
- gzip u-boot::
gzip u-boot-nodtb.bin
- Append dtb to gzipped u-boot::
cat u-boot-nodtb.bin.gz arch/arm/dts/your-board.dtb > u-boot-nodtb.bin.gz-dtb
- A ``qcom.its`` file can be found in ``board/qualcomm/generic/``
directory. It expects a folder as ``qcom_imgs/`` in the main directory
containing pre-built kernel, dts and ramdisk images. See ``qcom.its``
for full path to images::
mkimage -f qcom.its qcom.itb
- Now we've got everything to build android boot image::
mkbootimg --kernel u-boot-nodtb.bin.gz-dtb --ramdisk db845c.itb \
--output boot.img --pagesize 4096 --base 0x80000000
- Flash boot.img using fastboot and erase dtbo to avoid conflicts with our DTB:
.. code-block:: bash
fastboot flash boot boot.img
fastboot erase dtbo
.. _Samsung S9 page: https://en.wikipedia.org/wiki/Samsung_Galaxy_S9
.. _DragonBoard 845c page: https://www.96boards.org/product/rb3-platform/