Android/riscv64

What is this?

If you don't know what Android is, what risc-v is, or what they have to do with one another, start by reading Android and RISC-V: What you need to know to be ready.

This github project is solely for issue tracking/discussion/documentation purposes.

All Android/riscv64 work is being done directly in AOSP. Patches should be sent to AOSP using the usual AOSP contribution process and not as pull requests here.

You might also want to subscribe to the sig-android mailing list. (You need to send mail to sig-android+subscribe@lists.riscv.org and then click "Join" on the mailing list web site.)

Status

We're currently (2023Q4) still working on cuttlefish virtual devices and ART, although the shell and command-line tools (and all the libraries they rely on) have been working great for a while. ART works, but is currently interpreter-only, so quite slow. cuttlefish works, but you'll need qemu 8 (see the cuttlefish setup section below for more details).

You can see the current status of the riscv64 build in CI in the aosp_cf_riscv64_phone column (between arm64 and x86-64) of ci.android.com, but we're not currently (2023Q4) running the tests in CI.

Can I try it?

Download the source using the usual AOSP download process and then:

$ cd aosp
$ source build/envsetup.sh
$ lunch aosp_cf_riscv64_phone-trunk_staging-userdebug

============================================
PLATFORM_VERSION_CODENAME=UpsideDownCake
PLATFORM_VERSION=UpsideDownCake
TARGET_PRODUCT=aosp_cf_riscv64_phone
TARGET_BUILD_VARIANT=userdebug
TARGET_ARCH=riscv64
TARGET_ARCH_VARIANT=riscv64
TARGET_CPU_VARIANT=generic
HOST_OS=linux
HOST_OS_EXTRA=Linux-5.19.11-1rodete1-amd64-x86_64-Debian-GNU/Linux-rodete
HOST_CROSS_OS=windows
BUILD_ID=AOSP.MASTER
OUT_DIR=out
============================================
$ make -j

If you want to check whether a particular directory builds, cd into that directory and use mm -j.

(For more tips on building in general, see Building Android.)

Cuttlefish (emulator) setup

To launch cuttlefish, follow the general AOSP cuttlefish setup instructions.

(Note that in addition to the general setup mentioned above, if your host Linux distro doesn't already have it, you will have to apt install qemu-system-riscv64. If your host Linux distro's qemu version is too old -- we recommend 8.1.0, which is currently available in Debian testing -- you may need to build your own. In that case, you'll need the -qemu_binary_dir= option when calling launch_cvd to point it at the correct copy of qemu.)

Getting to a shell (faster, but no graphics)

After building, run this following command from the same shell:

$ launch_cvd -cpus=4 --memory_mb=8192

After about 10s you should be able to use adb shell to connect to your riscv64 cuttlefish!

Getting to the home screen (slower, but with graphics)

After building, run this following command from the same shell:

$ launch_cvd -cpus=8 --memory_mb=8192 --gpu_mode=drm_virgl

You can then use vncviewer localhost:6444 to connect to your riscv64 cuttlefish!

(Note that even on a fast Xeon workstation it takes several minutes to get to the boot animation and ten minutes to get to the home screen!)

How do I contribute?

Consult the regular AOSP Contributing documentation for more information on how to send us your patches.

Note that changes to projects under external/ (other than to Android.bp files) typically need to go to the upstream open source project in question first, and will then be merged into AOSP from there. In many cases, the METADATA file will point you to the upstream source, but feel free to ask here if not!

Review our Community Guidelines

This project follows Google's Open Source Community Guidelines.