Exynos and Rockchip devfreq event monitors
Small helper drivers that read memory-bus and performance counters on Samsung Exynos and Rockchip ARM SoCs, so the kernel's dynamic frequency scaling can tell how busy the memory controller is. They cover Exynos chips back to the 2013 Exynos 5420 and current Rockchip parts like RK3399, RK3568, and RK3588 found in single-board computers sold today.
recommendation
Worth keeping but documenting its scope: this directory provides the SoC-specific performance counters that feed dynamic frequency scaling on Samsung Exynos and Rockchip platforms. The Rockchip side covers chips still shipping in 2025 (RK3399, RK3568, RK3588 boards like the Radxa ROCK 5), and bug fixes were still landing in 2025-2026. The Exynos side covers older 2013-era silicon but was still being maintained through late 2024. There is no obvious replacement, since each backend is tied to vendor-specific hardware blocks.
repository signals
sources
- lore.kernel.org
`rockchip-dfi.c` still receives functional fixes in 2026, indicating active upstream maintenance rather than abandonment.
- lore.kernel.org
The Exynos event drivers were still being updated in late 2024 as part of devfreq/platform-driver API churn, showing they remain in the maintained kernel surface.
- news.samsung.com
Exynos 5420-era hardware tied to `exynos-nocp` is an older 2013 SoC generation, supporting the view that the Exynos portion is legacy hardware today.
- docs.radxa.com
RK3588/RK3588-S boards are current products, so the Rockchip portion of this directory maps to hardware still sold for new deployments.
codex reasoning notes (technical)
Local shell inspection showed three real platform drivers: `exynos-nocp`, `exynos-ppmu`, and `rockchip-dfi`, with DT compatibles spanning old Exynos blocks and newer Rockchip RK3399/RK3568/RK3588. `lore_activity` on `rockchip-dfi.c` returned 2025-2026 bug-fix traffic (source 1), and `lore_activity` on the Exynos files returned 2024 maintenance traffic (source 2); that argues against deprecation/removal. Web search produced Samsung's Exynos 5420 launch page (source 3) and Radxa's current ROCK 5 product line page (source 4), showing this directory mixes legacy Exynos support with currently sold Rockchip SoCs. No natural upstream replacement driver exists because these are SoC-specific devfreq event backends. `lore_file_timeline` on the directory path returned no directory-level hits, and a removal-focused `lore_regex` query timed out, so confidence is slightly below high; given active maintenance plus mixed-age deployments, `keep-annotate` fits better than `deprecate` or `remove`.