This demo duplicates the behavior of the Linux+FreeRTOS demo, with Zephyr taking the place of FreeRTOS. It features a dual guest configuration, i.e., Linux and Zephyr, connected through an inter-VM communication object. This object is implemented through a shared memory region and a doorbell mechanism in the form of hardware interrupts.
If Zephyr supports SMP for the target architecture, half of the cores are assigned to Zephyr and half to Linux. If not, one core is assigned to Zephyr and the remaining ones to Linux. The platform's first available UART is also assigned to Zephyr. Any additional UART device is assigned to Linux. The Linux guest is also accessible via ssh at the static address 192.168.42.15.
You can send messages to Zephyr by writing to /dev/baoipc0. For example:
echo "Hello, Bao!" > /dev/baoipc0
The Zephyr guest will also send a message to Linux each time it receives a
character in its UART. However, the Linux inter-VM is not configured for Linux
to asynchronously react to it and output this message. You can checkout the last
Zephyr message by reading /dev/baoipc0:
cat /dev/baoipc0
If you are targetting an MPU platform (i.e. fvp-r), set:
export FVPR_VM_IMAGES="$BAO_DEMOS_WRKDIR_IMGS/zephyr.bin@0x24000000 \
$BAO_DEMOS_WRKDIR_IMGS/linux.bin@0x28000000"