RISC-V Architecture Layer for OpenEmbedded/Yocto
This is the general hardware-specific BSP overlay for the RISC-V based devices.
More information can be found at: https://riscv.org/ (Official Site)
The core BSP part of meta-riscv should work with different OpenEmbedded/Yocto distributions and layer stacks, such as:
- Distro-less (only with OE-Core).
- Yoe Distro.
- Yocto/Poky.
This layer depends on:
- URI: https://github.com/openembedded/openembedded-core
- branch: master
- revision: HEAD
- URI: https://github.com/openembedded/bitbake
- branch: master
- revision: HEAD
Note: You only need this if you do not have an existing Yocto Project build environment.
Make sure to install the repo
command by Google first.
mkdir riscv-yocto && cd riscv-yocto
repo init -u https://github.com/riscv/meta-riscv -b master -m tools/manifests/riscv-yocto.xml
repo sync
repo start work --all
In order to bring all the layers up to date with upstream
cd riscv-yocto
repo sync
repo rebase
. ./meta-riscv/setup.sh
Kas build is supported, you can run the following commands:
git clone https://github.com/riscv/meta-riscv.git -b kirkstone
cd meta-riscv
- For basic
qemuriscv64
build run:
kas build kas/base-riscv.yml
base-riscv.yml will build core-image-minimal
, you can then boot it with:
runqemu core-image-minimal nographic
NOTE nographic
is needed for this image, because it has no graphical support for graphical Qemu run.
- For
nezha
build:
kas build kas/nezha.yml
- For
beaglev
build:
kas build kas/beaglev.yml
- For more machines check
kas
folder.
If you have your own layer that depends on this layer, you can create a kas yml
file in your layer with the following content (nezha
build as an example):
head:
version: 8
includes:
- repo: meta-riscv
file: kas/nezha.yml
repos:
meta-riscv:
url: https://github.com/riscv/meta-riscv.git
path: layers
refspec: kirkstone
target: custom-image # Or nezha default image: riscv-nezha-image
For more details on nezha
, beaglev
and other boards steps check doc
folder.
The different machines you can build for are:
- freedom-u540: The SiFive HiFive Unleashed board
- beaglev-starlight-jh7100: BeagleV - Based on Starlight JH7100 SOC
- mangopi-mq-pro: MangoPi MQ Pro - Based on Allwinner D1 SOC
Note that this layer also provides improvements and features for the upstream qemuriscv32 and qemuriscv64 machines.
Additional beagleV notes on bringup are here
A console-only image for the 64-bit QEMU machine
MACHINE=qemuriscv64 bitbake core-image-full-cmdline
MACHINE=beaglev-starlight-jh7100 bitbake core-image-full-cmdline
To build an image to run on the HiFive Unleashed using Wayland run the following
MACHINE=freedom-u540 bitbake core-image-weston
To build an image to run on the BeagleV using Wayland run the following
MACHINE=beaglev-starlight-jh7100 bitbake core-image-weston
To build an image to run on the MangoPi MQ Pro (console only has been tested so far) run the following:
MACHINE=mangopi-mq-pro bitbake core-image-base
To build a full GUI equipped image running Plasma Mobile see the in-tree documentation here.
Run the 64-bit machine in QEMU using the following command:
MACHINE=qemuriscv64 runqemu nographic
Run the 32-bit machine in QEMU using the following command:
MACHINE=qemuriscv32 runqemu nographic
If you would like to boot the images from a TFTP server (optional) you should set your TFTP server address in your local.conf with the following line. Change 127.0.0.1
to the IP address of your TFTP server and copy the uImage to the server.
TFTP_SERVER_IP = "127.0.0.1"
To use the Microsemi expansion board with your HiFive Unleased add the following line to your local.conf. This tells the Unleashed to use a device tree with the PCIe device described:
RISCV_SBI_FDT:freedom-u540 = "hifive-unleashed-a00-microsemi.dtb"
The output of the build can also be written to an SD card using bmaptool, the steps to do this are below:
$ MACHINE=freedom-u540 wic create freedom-u540-opensbi -e core-image-minimal
$ bmaptool create ./freedom-u540-opensbi-201812181337-mmcblk.direct > image.bmap
$ sudo bmaptool copy --bmap image.bmap ./freedom-u540-opensbi-201812181337-mmcblk.direct /dev/sdX
The output of a freedom-u540
, beaglev-starlight-jh7100
or mangopi-mq-pro
build will be a <image>.wic.gz
file. You can write this file to an sd card using:
$ zcat <image>-<machine>.wic.gz | sudo dd of=/dev/sdX bs=4M iflag=fullblock oflag=direct conv=fsync status=progress
Instead of dding wic.gz image bmaptool
(available in most Linux distributions and/or pip) can be used for more reliable and faster flashing. You can write this file to an sd card using:
$ sudo bmaptool copy <image>-<machine>.wic.gz /dev/sdX
- Khem Raj
<raj dot khem at gmail.com>