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.
This layer depends on:
- URI: git://github.com/openembedded/openembedded-core
- branch: master
- revision: HEAD
- URI: git://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 git://github.com/riscv/meta-riscv -b master -m tools/manifests/riscv-yocto.xml repo sync repo start work --all
Update existing workspace
In order to bring all the layers up to date with upstream
cd riscv-yocto repo sync repo rebase
Setup Build Environment
The different machines you can build for are:
- freedom-u540: The SiFive HiFive Unleashed board
- beaglev-starlight-jh7100: BeagleV - Based on Starlight JH7100 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 a full GUI equipped image running Plasma Mobile see the in-tree documentation here.
Running in QEMU
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
Running on hardware
Setting up a TFTP server
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"
Running with the Microsemi Expansion board
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"
Sparse Image Creation
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
beaglev-starlight-jh7100 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
- Khem Raj
<raj dot khem at gmail.com>