SM8x50 (Snapdragon 8 Gen devboards)

Note

sm8x50-userdebug is an AOSP build target for Snapdragon 8 Gen devboards. It is supported only on v6.8+ kernel versions. Primarily supported and tested on sm8550-hdk. Other Snapdragon 8 Gen devboards like sm8450-qrd, sm8450-hdk, sm8550-qrd, sm8650-qrd, and sm8650-hdk are supported on the best efforts basis.

SM8550-HDK is a Snapdragon 8 Gen 2 Mobile Hardware Development Kit.

Getting started with SM8550-HDK

The power-up sequence for sm8550-hdk is similar to that of RB3 and RB5. The wall power need to be switched ON first and then connect the USB-C to boot automatically without pressing any physical button on the board. Make sure that switch <7, 8> of S5702 is ON before powering ON the device to enable HDMI out.

sm8x50-userdebug boots to UI with v6.8+ android-mainline and upstream kernel using software rendering and linux-firmware binaries for now. lunch target is not added yet and will be added as soon the firmware binaries land in linaro-vendor / linux-firmware repo to make sure that the device has more features enabled and is in a more usable state. Boot image header v2 is used for now, while we are working on releasing ABL with header v4 support.

Compile AOSP from sources for SM8x50 (Snapdragon 8 Gen) devices

mkdir $AOSP
cd $AOSP
repo init -u https://android.googlesource.com/platform/manifest -b master
repo sync -j`nproc`
./device/linaro/dragonboard/fetch-vendor-package.sh
cd device/linaro/dragonboard
git remote add d4a https://source.devboardsforandroid.linaro.org/device/linaro/dragonboard
git fetch d4a; git checkout d4a/d4a
cd $AOSP
source ./build/envsetup.sh
lunch sm8x50-trunk_staging-userdebug
make -j`nproc`

The above instructions will build AOSP images for sm8x50 devboards. This default build supports booting from an mmc-sdcard (due to upstream UFS bugs currently being looked at) and will boot to UI using software rendering support.

Flashing and booting AOSP from mmc-sdcard

Reboot sm8x50 in fastboot mode and run following commands to disable verity verity and and erase AOSP partitions for any stale images and to make sure that every reboot/reset lands at the ABL fastboot mode prompt.

$AOSP/external/avb/avbtool.py make_vbmeta_image --flag 2 --padding_size 4096 --output ./vbmeta_disabled.img
fastboot --disable-verity --disable-verification flash vbmeta ./vbmeta_disabled.img
fastboot erase boot erase dtbo erase init_boot erase vendor_boot
fastboot reboot bootloader

Booting AOSP from a mmc sdcard is an experimental build configuration and is only intended to be used in the LKFT lab. But booting from mmc-sdcard is the default option on SM8550-HDK due to some upstream UFS breakages.

We chainload U-Boot from ABL bootloader and flash the, already plugged-in, mmc-sdcard. For now we are using a WIP upstream u-boot fork.

mmc boot configuration require atleast 16GB sdcard. Here are the instructions to prepare and flash AOSP images on a MMC sdcard:

Note

Following commands that are listed with => prompt means those commands need to be run from the u-boot prompt on the device and commands with $ means they need to be run from the HOST machine.

Build U-Boot for SM8550-HDK and boot with it:

$ git clone https://source.devboardsforandroid.linaro.org/platform/external/u-boot -b wip/rbx-integration
$ cd u-boot
$ make CROSS_COMPILE=aarch64-linux-gnu- clean qcom_defconfig all
$ gzip u-boot-nodtb.bin
$ mkbootimg --os_version 14.0.0 --os_patch_level 2023-10 --header_version 2 \
  --kernel u-boot-nodtb.bin.gz --dtb dts/upstream/src/arm64/qcom/sm8550-hdk.dtb \
  --pagesize 2048 --cmdline "" --output u-boot.img
$ fastboot set_active a boot u-boot.img                                                               # this will boot U-Boot on sm8550-hdk

Prepare AOSP partition layout on the sdcard from the U-Boot prompt. Make sure that a 16GB+ MMC sdcard is plugged into the board:

=> run gpt_mmc_aosp
=> reset                          # this will reboot in ABL fastboot mode
$ fastboot set_active a boot u-boot.img
=> run fastboot                   # starting U-Boot's fastboot command
$ fastboot erase boot erase init_boot erase vendor_boot erase modemst1 erase modemst2 erase fsg erase fsc erase misc erase metadata erase super erase userdata
$ fastboot reboot                 # rebooting in ABL fastboot mode
$ fastboot set_active a boot u-boot.img
=> run fastboot

To flash images on the MMC sdcard, make sure we run U-Boot’s fastboot command on the device before running the following flash and boot commands:

cd out/target/product/sm8x50
fastboot flash super ./super.img flash userdata ./userdata.img format:ext4 metadata reboot
fastboot set_active a boot ./boot.img

Note

We do not flash boot.img on the sdcard; instead, we load the boot image from device RAM by running fastboot set_active a boot boot.img.

It should boot sm8x50 devices to UI with software rendering support.

Note

To boot from the on-board UFS, build AOSP images with TARGET_SDCARD_BOOT=false build flag and follow the same flashing and booting instructions as above.

Flashing and booting AOSP from mmc-sdcard using Generic Bootloader Library (GBL)

Note

This configuration is tested only on RB3, RB5 and SM8550-HDK. Booting AOSP from a mmc sdcard using GBL is an experimental build configuration and is only intended to be used in the LKFT lab.

Reboot sm8x50 in fastboot mode and run following commands to disable verity and erase AOSP partitions for any stale images to make sure that every reboot/reset lands at the ABL fastboot mode prompt.

$ $AOSP/external/avb/avbtool.py make_vbmeta_image --flag 2 \
  --padding_size 4096 --output ./vbmeta_disabled.img                                     # prepare vbmeta_disabled.img
$ fastboot --disable-verity --disable-verification flash vbmeta ./vbmeta_disabled.img    # disable verity
$ fastboot erase boot erase dtbo erase init_boot erase vendor_boot
$ fastboot reboot bootloader

We chainload U-Boot from ABL bootloader and flash the, already plugged-in, mmc-sdcard. For SM8550-HDK, we are using a WIP upstream u-boot fork with GBL specific changes. Here are the instructions to prepare, flash and boot AOSP images from a mmc-sdcard using GBL. mmc-sdcard boot configuration require atleast 16GB sdcard.

Note

Following commands that are listed with => prompt means those commands need to be run from the u-boot prompt on the device and commands with $ means they need to be run from the HOST machine.

Build U-Boot for SM8550-HDK and boot with it:

$ git clone https://source.devboardsforandroid.linaro.org/platform/external/u-boot -b wip/rbx-integration
$ cd u-boot
$ make CROSS_COMPILE=aarch64-linux-gnu- clean qcom_defconfig all
$ gzip u-boot-nodtb.bin
$ mkbootimg --os_version 14.0.0 --os_patch_level 2023-10 --header_version 2 \
  --kernel u-boot-nodtb.bin.gz --dtb dts/upstream/src/arm64/qcom/sm8550-hdk.dtb \
  --pagesize 2048 --cmdline "" --output u-boot.img
$ fastboot set_active a boot u-boot.img                                                               # this will boot U-Boot on sm8550-hdk

Build GBL efi app and mcopy it over to the gbl.img:

$ repo init -u https://android.googlesource.com/kernel/manifest -b uefi-gbl-mainline
$ repo sync -j`nproc`
$ ./tools/bazel run //bootable/libbootloader:gbl_efi_dist \
  --extra_toolchains=@gbl//toolchain:all --sandbox_debug --verbose_failures
$ dd if=/dev/zero of=gbl.img bs=1048576 count=2
$ mkfs.vfat gbl.img
$ mcopy -i gbl.img out/gbl_efi/gbl_aarch64.efi ::gbl_aarch64.efi

Build AOSP images with GBL support (boot image header v4 support with init_boot):

$ mkdir $AOSP
$ cd $AOSP
$ repo init -u https://android.googlesource.com/platform/manifest -b master
$ repo sync -j`nproc`
$ ./device/linaro/dragonboard/fetch-vendor-package.sh
$ cd device/linaro/dragonboard
$ git remote add d4a https://source.devboardsforandroid.linaro.org/device/linaro/dragonboard
$ git fetch d4a; git checkout d4a/d4a
$ cd $AOSP
$ source ./build/envsetup.sh
$ lunch sm8x50-trunk_staging-userdebug
$ make TARGET_SDCARD_BOOT=true TARGET_USES_GBL=true -j`nproc`

The above instructions will build AOSP images (boot.img, init_boot.img, super.img, userdata.img and vendor_boot.img) for sm8x50 devboards under $AOSP/out/target/product/sm8x50 directory.

Prepare AOSP partition layout, flash and launch GBL and boot AOSP images on the sdcard. Make sure that a 16GB+ MMC sdcard is plugged into the board:

=> run gpt_mmc_aosp                                                                      # prepare AOSP style GPT partition layout
                                                                                         # on the mmc-sdcard
=> reset                                                                                 # this will reboot in ABL fastboot mode
$ fastboot set_active a boot u-boot.img                                                  # reboot U-Boot on sm8550
=> run fastboot                                                                          # starting U-Boot's fastboot command
$ fastboot erase gbl erase boot_a erase boot_b erase init_boot_a \
  erase init_boot_b erase vendor_boot_a erase vendor_boot_b \
  erase vbmeta_a erase vbmeta_b erase modemst1 erase modemst2 \
  erase fsg erase fsc erase misc erase metadata erase super erase userdata               # erase mmc-sdcard partitions
$ fastboot flash gbl ./gbl.img flash boot ./boot.img \
  flash init_boot ./init_boot.img flash vendor_boot ./vendor_boot.img \
  flash super ./super.img flash userdata ./userdata.img format:ext4 metadata             # flash GBL and AOSP images
$ fastboot --disable-verity --disable-verification flash vbmeta_a ./vbmeta_disabled.img  # disable verity
$ fastboot --disable-verity --disable-verification flash vbmeta_b ./vbmeta_disabled.img  # disable verity on _b slot as well just in case
$ fastboot reboot
$ fastboot set_active a boot u-boot.img                                                  # reboot U-Boot on sm8550
=> run gbl                                                                               # launch GBL

Note

The above “run gbl” command from U-Boot prompt will launch GBL and it will start booting the newly flashed AOSP images to UI with software rendering support, unless you press Backspace to interrupt the GBL launch and force it into the fastboot mode over USB.

Building and booting with custom kernel

The Preferred option is to build Android GKI kernel artifacts using official Bazel build instructions.

Build android-mainline kernel for SM8x50 devices

Run the following commands to clone the android-mainline repo including the kernel source, prebuilt Android toolchains and build scripts.

mkdir gki-repo
cd gki-repo
repo init -u https://android.googlesource.com/kernel/manifest -b common-android-mainline
repo sync -j`nproc`
tools/bazel clean
tools/bazel run //common:db845c_dist

Now delete all the objects in $(AOSP_TOPDIR)device/linaro/dragonboard-kernel/android-mainline/, then copy build artifacts from out/db845c/dist/ to $(AOSP_TOPDIR)/device/linaro/dragonboard-kernel/android-mainline/

Then rebuild AOSP and boot with new boot.img using:

make TARGET_KERNEL_USE=mainline bootimage -j`nproc`'
fastboot set_active a boot ./boot.img

Download and build upstream tracking kernel

git clone https://git.linaro.org/people/amit.pundir/linux -b rbX-mainline
cd linux
make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- mrproper
KCONFIG_CONFIG=./arch/arm64/configs/temp_aosp_rbx_sm8x50_defconfig ./scripts/kconfig/merge_config.sh -m -r ./arch/arm64/configs/aosp_defconfig ./kernel/configs/aosp_rbx_sm8x50.config
make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- temp_aosp_rbx_sm8x50_defconfig
make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- DTC_FLAGS=-@ -j`nproc`
make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- INSTALL_MOD_PATH=./modules/ INSTALL_MOD_STRIP=1 modules_install -j`nproc`
rm arch/arm64/configs/temp_aosp_rbx_sm8x50_defconfig
cp arch/arm64/boot/Image.gz arch/arm64/boot/dts/qcom/qrb5165-rb5.dtb arch/arm64/boot/dts/qcom/sdm845-db845c.dtb arch/arm64/boot/dts/qcom/sm8450-hdk.dtb arch/arm64/boot/dts/qcom/sm8450-qrd.dtb arch/arm64/boot/dts/qcom/sm8550-hdk.dtb arch/arm64/boot/dts/qcom/sm8550-qrd.dtb arch/arm64/boot/dts/qcom/sm8650-hdk.dtb arch/arm64/boot/dts/qcom/sm8650-qrd.dtb $AOSP/device/linaro/dragonboard-kernel/android-upstream/
find ./modules/lib/ -iname \*.ko -exec cp {} $AOSP/device/linaro/dragonboard-kernel/android-upstream/ \;

Then rebuild AOSP and boot with new boot.img using:

make TARGET_KERNEL_USE=upstream bootimage -j`nproc`'
fastboot boot ./boot.img

Known issues and Troubleshooting on sm8550-hdk

Fastboot over U-Boot takes about 30seconds to initialize on the HOST machine after running “run fastboot” command on the U-Boot shell.
UFS is not stable. There are a series of known issues that are currently being worked upon.

For example: Probability of UFS probe running into a hard crash during boot time is very high and it needs a power reset to recover.

And then there is a run time UFS crash which leaves the device unusable.
At times fastboot boot run into the following failure:

fastboot boot ./boot.img
Sending 'boot.img' (19988 KB)                      OKAY [  0.460s]
Booting                                            FAILED (remote: 'Failed to load/authenticate boot image: Load Error')
fastboot: error: Command failed

Run the following set of commands to recover from the above error:

fastboot reboot bootloader
fastboot set_active a boot ./boot.img

Device Maintainer(s)

Amit Pundir <pundir at #aosp-developers on OFTC IRC>