SiFive BSPs layer for OpenEmbedded/Yocto
This is the general hardware-specific BSP layer for the SiFive boards.
More information can be found at: https://sifive.com/ (Official Site)
This layer depends on:
mkdir dist && cd dist
git clone https://github.com/sifive/meta-sifiveThis layer provides a BSP for the following machines:
freedom-u540: The SiFive HiFive Unleashed boardunmatched: The Sifive Unmatched board
But changes are also validated on Qemu RISC-V 64bits, so this layer also provide a Kas yaml to build this machine.
This layer doesn't define new distributions.
BSPs are validated with the core-image-minimal and the core-image-sato
provides by the OE-core layer.
Building disk images is CPU intensive, could require <10GB of sources downloaded over the Internet and <200GB of local storage.
This layer provides Kas scripts configured to download and to configure the
build environment to build core-minimal images for supported targets:
kas build --update ./meta-sifive/scripts/kas/freedom-u540.yml
kas build --update ./meta-sifive/scripts/kas/qemuriscv64.yml
kas build --update ./meta-sifive/scripts/kas/unmatched.ymlMoreover, it is also possible to build other images, or SDK, or also packages, for example:
kas build --update ./meta-sifive/scripts/kas/unmatched.yml --target core-image-weston
kas build --update ./meta-sifive/scripts/kas/unmatched.yml --target buildtools-extended-tarball
kas build --update ./meta-sifive/scripts/kas/unmatched.yml --target busybox
kas shell --update ./meta-sifive/scripts/kas/unmatched.yml -c "bitbake core-image-minimal -c populate_sdk"
kas shell --update ./meta-sifive/scripts/kas/unmatched.yml -c "bitbake core-image-minimal -c populate_sdk_ext"The OpenEmbedded/Yocto framework provides a wrapper for QEMU, named runqemu in order to use it easily.
Below examples to use this Qemu over a Kas shell:
kas shell ./meta-sifive/scripts/kas/qemuriscv64.yml -c "runqemu slirp nographic core-image-minimal"
kas shell ./meta-sifive/scripts/kas/qemuriscv64.yml -c "runqemu slirp serialstdio core-image-sato"The OpenEmbedded/Yocto framework provides also provides tools to implement and to run tests.
These tests can be executed on all supported targets, using the following commands:
kas build --update ./meta-sifive/scripts/kas/qemuriscv64.yml:./meta-sifive/scripts/kas/include/test.yml
kas shell --update ./meta-sifive/scripts/kas/qemuriscv64.yml:./meta-sifive/scripts/kas/include/test.yml -c "bitbake core-image-minimal -c populate_sdk && bitbake core-image-minimal -c testsdk"
kas shell --update ./meta-sifive/scripts/kas/qemuriscv64.yml:./meta-sifive/scripts/kas/include/test.yml -c "bitbake core-image-minimal -c populate_sdk_ext && bitbake core-image-minimal -c testsdkext"
kas shell --update ./meta-sifive/scripts/kas/qemuriscv64.yml:./meta-sifive/scripts/kas/include/test.yml -c "resulttool report ./tmp-glibc/log/oeqa"You will find all available build fragments (incl. disk images) in
$BUILDDIR/tmp/deploy/images/$MACHINE where MACHINE can be:
freedom-u540qemuriscv64unmatched
Disk images files use <image>-<machine>.<output_format> format, for example,
core-image-minimal-unmatched.wic.xz. We are interested in .wic.xz disk
images for writing to uSD card.
Be very careful while picking /dev/sdX device! Look at dmesg, lsblk, blkid, GNOME Disks, etc. before and after plugging in your uSD card to find a proper device. Double check it to avoid overwriting any of system disks/partitions!
Unmount any mounted partitions from uSD card before writing!
Images built can be flashed with bmaptool (faster), for example:
sudo bmaptool copy ../build/tmp-glibc/deploy/images/unmatched/core-image-minimal-unmatched.rootfs.wic.xz /dev/mmcblk0Otherwise, you can also use the dd command, for example:
xzcat ../build/tmp-glibc/deploy/images/unmatched/core-image-minimal-unmatched.rootfs.wic.xz | sudo dd of=/dev/mmcblk0 bs=512K iflag=fullblock oflag=direct conv=fsync status=progressYou will need to modify MSEL to allow using U-Boot SPL, OpenSBI, U-Boot proper bootloaders from uSD card instead of SPI-NOR Flash chip:
USB LED Mode Select Ethernet
+===|___|==****==+-+-+-+-+-+-+=================|******|===+
| | | | | |X| | | | |
| | | | | | | | | | |
| HFXSEL->|X|X|X|X| |X| |______| |
| +-+-+-+-+-+-+ |
| RTCSEL-----/ 0 1 2 3 <--MSEL |
| |
By default MSEL on Unmatched is set to use uSD instead of SPI-NOR Flash chip to load U-Boot SPL, OpenSBI and U-Boot proper. Below is the default configuration for DIP switches (located next to Assembly Number and RTC battery):
+----------> CHIPIDSEL
| +--------> MSEL3
| | +------> MSEL2
| | | +----> MSEL1
| | | | +--> MSEL0
| | | | |
+-+-+-+-+-+
| |X| |X|X| ON(1)
| | | | | |
|X| |X| | | OFF(0)
+-+-+-+-+-+
BOOT MODE SEL
Connect your HiFive Unleashed or HiFive Unmatched to your PC using microUSB-USB cable to access serial console.
For macOS, run: screen -L /dev/tty.usbserial-*01 115200
For Linux, run: screen -L /dev/serial/by-id/usb-FTDI_Dual_RS232-HS-if01-port0 115200
The above commands might vary depending on your exact setup.
-L command will log all output to screenlog.0 in your current working directory.
To quit screen, hit Ctrl - A followed by \ symbol. Finally agree to
terminate all windows by typing y.
You can login with root account. The password is sifive. We strongly
recommend to change the default password for the root account on the first
boot before you connect it to the Internet.
Before you connect your board to the Internet we strongly recommend to change the default password for the root account and configure your network equipment (for example, routers and firewalls) appropriately.
SSH daemon is enabled by default, in order to be able to execute remotely runtime tests. To disable SSH daemon connect to the board using serial console method described above. Once connected execute the following commands:
systemctl disable sshd.socket
systemctl stop sshd.socket
The HiFive Unleashed and Unmatched behave like any other network capable
device (such as PC, laptop, and Single Board Computers like Raspberry Pi).
Connect the board to your network (for example, a router), and it will acquire
IPv4 + DNS configuration using DHCP protocol. You can use your router
management panel to get assigned IPv4 address or use the serial console to
acquire it directly from the board (use ip addr command to print active
network information). Finally you can SSH to the board:
ssh -o PreferredAuthentications=password -o PubkeyAuthentication=no -o StrictHostKeyChecking=no -o "UserKnownHostsFile /dev/null" root@<IPv4>
Various GPUs from AMD were successfully tested with the boards. In particular Radeon HD 6450 is the most widely used. Other GPUs from the same family might also work, for instance, THD64xxM, HD7450, HD8450, R5 230, R5 235, R5 235X. The newest tested GPUs from AMD are RX 550, RX 570, RX 580 with no issues.
It is highly advised to resize partitions offline (i.e. before booting the system). If you already booted the system and cannot do offline resizing then the following instructions should resize rootfs (root file partition) to full uSD capacity:
sgdisk -v /dev/mmcblk0
sgdisk -e /dev/mmcblk0
parted /dev/mmcblk0 resizepart 4 100%
resize2fs /dev/mmcblk0p4
syncThis is an experimantal feature currently only available on SiFive HiFive Unmatched board. This allow sharing a block device over the network. This is not an extensive guide into NBD, but a quick start.
If you want to use this feature open extlinux.conf in /boot partition and
modify the append line to:
append ip=dhcp root=/dev/nbd0 rw nbdroot=<server_ip_address>:<export_name> nbdport=10809 console=ttySIF0,115200 earlycon
If you are booting directly from U-Boot prompt, you would need to set
bootargs variable instead.
Note that <export_name> value might be ignored by the NBD server (depends on
the implementation and configuration).
nbdkit is a recommended NBD server for it's flexibility.
Here is an example command for nbdkit:
sudo nbdkit -f --verbose --threads 128 --filter=cow --filter=partition --filter=xz file core-image-minimal-unmatched-<..>.rootfs.wic.xz partition=4
This would expose the ext4 filesystem on the 4th partition from XZ compressed
disk image. By default it's read-only thus we also add a COW (Copy-on-Write)
layer. Note that COW layer is not saved by default and will be lost if
nbdkit process is terminated. See
nbdkit-cow-filter NOTES on
how to save disk image with all the modifications for further use.
Using XZ compressed disk image is convenient, but doesn't deliver high performance. For higher performance uncompress disk image before sharing it via NBD.
Here is another example:
sudo mkdir rootfs
sudo tar -xJ --numeric-owner -C rootfs -f core-image-minimal-unmatched-<..>.rootfs.tar.xz
sudo nbdkit -f --verbose --threads 128 --filter=partition --filter=cow linuxdisk $PWD/rootfs size=+2G partition=1
In this particular case we uncompress rootfs into a directory. We ask nbdkit
to take the directory, generate linux disk image from it, add some additional
free space, add a COW layer to make it writable and send "naked" filesystem
(i.e. no partition table) as before.
nbdkit has a number of plugins and filters allowing various ways how to share
disk images over the network.
cd /usr/share/tensorflow/lite/examples/python/
python3 python3 mnist.py
If you want to file issues, send patches and make feature/enhancement requests use meta-sifive repository on GitHub. So that the maintainer can process your request.
You are also welcome to join SiFive Forums where we have HiFive Unleashed and HiFive Unmatched categories for discussions.