Amlogic Meson Secure Monitor firmware interface
The low-level bridge between Linux and the secure-world firmware running on Amlogic Meson SoCs, the chips found in many Android TV boxes and single-board computers like the Khadas VIM series. It lets the kernel ask the secure monitor to read fused chip data, control power domains, and perform thermal calibration on Amlogic-based devices.
recommendation
It should stay in the kernel because it is the active interface Linux uses to talk to the secure-world firmware on Amlogic Meson SoCs, and other in-tree subsystems (nvmem, power domains, thermal calibration) depend on it. Hardware in this family is still sold new in 2025 on boards like the Khadas VIM4 (Amlogic A311D2), and upstream development is ongoing, including a 2026 patch series adding new secure-monitor calls.
repository signals
sources
- lore.kernel.org
Upstream work is still active in 2026; the driver received a v5 feature patch adding a new secure-monitor thermal calibration call.
- khadas.com
Khadas still sells the VIM4 new, and it is based on an Amlogic A311D2 SoC.
- docs.khadas.com
Current Khadas documentation describes VIM4 as an Amlogic A311D2/A311D2-N0D SBC, indicating ongoing supported deployment of this SoC family.
- git.kernel.org
The directory is the in-tree "Amlogic Secure Monitor driver", i.e. real runtime hardware/firmware support rather than test or helper code.
codex reasoning notes (technical)
`exec_command` read local Kconfig/source and showed this is the Amlogic Secure Monitor driver, with in-tree consumers in nvmem and power-domain code; `lore_file_timeline` on `drivers/firmware/meson/meson_sm.c` showed sustained activity through 2026, including the cited v5 patch, so this is not an abandoned legacy block. `web.search_query` found an active Khadas VIM4 retail page and current docs for A311D2-based boards, supporting continued new-hardware availability. No natural replacement driver exists; this is the platform-specific SM firmware interface used by dependent Meson subsystems.