Hello,
As discussed during the meeting. Nicolas (intern in ST) is working on a POC for the interprocessor commination based on VIRTIO MMIO. The purpose of the POC is to be able to access from Linux to an I2C bus managed by the coprocessor.
Hardware: - a stm32mp157F DK board - a Nucleo shield ISK01A2 with a set of sensors, connected on the I2C bus - 2 SSD1306 displays connected on the I2C bus
Software - The transport layer is the VIRTIO MMIO - The Linux driver used is the virtio-i2c driver - on coprocessor a Zephyr is running that manages one of the displays and provides a bridge to the physical I2C bus
Source code: https://github.com/Nicolas62x/linux/commits/I2C-demo https://github.com/Nicolas62x/zephyr_stm32mp1/tree/I2C_demo
Please notice that it is only a POC so for time being. The main objective in this first step was to list issues in Linux kernel that should be addressed for the convergence. Nicolas should focus in coming month(s) on the coprocessor part (Zephyr and OpenAMP) to implement a virtio-2c device and the virtio-mmio device part based on Dan's work.
Regards, Arnaud
ST Restricted