AMD Versal CDX bus for adaptive SoC FPGA fabric
CDX is the bus framework that lets the embedded CPUs inside AMD's Versal and Versal Net adaptive SoCs discover and talk to devices implemented in the chip's reconfigurable FPGA fabric. It targets specialized embedded and accelerator hardware that AMD (formerly Xilinx) is still actively shipping in 2025 and beyond.
recommendation
It should stay because it is the bus layer for current AMD Versal Net silicon that is still being launched and sold, including the Versal Premium Series Gen 2 announced in late 2024. Maintainers are actively responding to bug reports and modernization patches into 2025 and 2026, and there is no alternative driver that could replace it for this hardware class. Deployment is niche, limited to embedded and adaptive-computing users, but the subsystem is healthy.
repository signals
sources
- spinics.net
v10 upstream patch series introduced the AMD CDX bus in 2023 for dynamically discovered FPGA fabric devices exposed to embedded CPUs.
- spinics.net
In July 2025, upstream discussion showed an actively reproduced linux-next build issue in drivers/cdx with an explicit maintainer response promising a fix, indicating ongoing maintenance rather than removal.
- mail-archive.com
A March 2026 patch updated drivers/cdx/cdx.c to use generic driver_override infrastructure, showing post-merge bug-fix attention in current development.
- cateee.net
LKDDb maps the CDX controller to OF compatible xlnx,versal-net-cdx and shows support present from Linux 6.4 through current HEAD.
- ir.amd.com
AMD announced new Versal Premium Series Gen 2 devices in November 2024, supporting that the broader Versal family was still being launched and sold into 2025.
codex reasoning notes (technical)
Local shell inspection of drivers/cdx shows a real bus subsystem for AMD FPGA devices, with comments in cdx.c identifying CDX as AMD FPGA architecture and recent local git history through 2026-02-04. Web search found no removal/deprecation thread; instead it found 2025-2026 maintenance traffic on spinics/mail-archive and LKDDb entries tying the driver to xlnx,versal-net-cdx. AMD product/IR pages obtained by web search show Versal family hardware still marketed/new in 2025+, so this is not legacy-only. Deployment is likely low rather than medium/high because CDX targets specialized embedded/adaptive-SoC fabric use, not commodity PCs/servers. No natural replacement driver exists because CDX is the bus framework for this hardware class.