MStar/SigmaStar MSC313 SoC PLL clock controllers
On-chip PLL clock generators for the MStar (later SigmaStar) MSC313 family of ARM system-on-chips, used mostly in low-cost IP security cameras and similar embedded devices from the late 2010s onward. The code provides the CPU and main PLL building blocks the rest of the SoC's clock tree hangs off of.
recommendation
Worth keeping but flagging as niche. The MSC313 lives on mainly in aftermarket IP-camera firmware projects like OpenIPC rather than in any actively sold mainstream product, but the code still receives upstream maintenance (an API-cleanup patch landed as recently as August 2025) and there is no alternative driver for this SoC's clock block. Removing it would break the only path to running mainline Linux on these chips, so a comment marking it as legacy/community-supported is more appropriate than deprecation.
repository signals
sources
- lore.kernel.org
The driver saw an upstream functional/API-maintenance patch in August 2025 for `msc313-cpupll`, so it is not fully abandoned.
- lore.kernel.org
The MPLL support was introduced specifically for MStar/SigmaStar MSC313-family hardware in the upstream clock subsystem.
- openipc.org
OpenIPC still lists MStar MSC313E among supported camera SoCs, indicating ongoing niche deployment in aftermarket IP-camera use.
codex reasoning notes (technical)
Local source inspection (`exec_command`) shows both files are SoC-specific PLL drivers for `mstar,msc313-*`, and Kconfig describes them as MStar/SigmaStar SoCs. `lore_activity` on `clk-msc313-cpupll.c` produced the 2025 linux-clk patch URL; `lore_activity` on `clk-msc313-mpll.c` produced the 2021 introduction URL. A fast `lore_file_timeline` on the directory returned no directory-level history signal, and no removal evidence surfaced in the limited lore checks. `web.search_query` + `open` produced the OpenIPC URL showing MSC313E in current community firmware support, which suggests low but non-zero legacy deployment. Because upstream still does occasional maintenance and there is no natural replacement for this SoC-specific clock block, removal/deprecation looks premature; annotate as legacy/niche instead.