AI Processing Unit "APU" Driver For Linux DRM Is Among The Latest Accelerator Drivers

Sent out last week by Alexandre Bailon with Bay Libre is the AI Processing Unit "APU" Direct Rendering Manager driver to interface between CPUs and AI Processing Units. The hope is this APU driver could be re-used by various hardware drivers while the initial focus is on bringing up the AI capabilities of the MediaTek MT8183 SoC.

While there is already the accelerator "accel" framework that is a subsidary of the DRM subsystem, the new proposal from Bay Libre developers is having this APU driver to further along this growing field of AI/accelerator kernel drivers. Bailon wrote in the initial patch series:

"This adds a DRM driver that implements communication between the CPU and an APU. The driver target embedded device that usually run inference using some prebuilt models. The goal is to provide common infrastructure that could be re-used to support many accelerators. Both kernel, userspace and firmware tries to use standard and existing to leverage the development and maintenance effort. The series implements two platform drivers, one for simulation and another one for the mt8183 (compatible with mt8365)."

The proposed DRM_APU Kconfig help text goes on to add:

"This provides a DRM driver that provides some facilities to communicate with an AI Processor Unit (APU). The driver intends to provide a common infrastructure that may be used to support many different APU."

Besides some technical issues being raised in the early code review, some objections have been raised over just naming this driver "APU". Some suggestions were made for possibly calling it apu_if or tiny_apu instead. We'll see what comes of this effort. Those interested can see the initial patch series to learn more about the APU driver as the latest open-source effort in the growing field of AI accelerator drivers.

Among other ongoing open-source AI kernel drivers are for Intel Habana Labs as the most notable and robust driver in this field followed by the new Intel Versatile Processing Unit (iVPU) for Meteor Lake, and also drivers from Qualcomm, Toshiba, and others being in various stages of development.