linux-drivers/
drivers/clocksource

SoC and hypervisor clocksource and timer drivers

A collection of timekeeping drivers covering hardware timer blocks built into modern SoCs and synthetic timers exposed by hypervisors. It includes the Arm Generic Timer used by virtually every Arm server, phone, and embedded board shipping today, Microsoft Hyper-V reference and synthetic timers for Linux guests, and many vendor-specific timer peripherals.

keep conf=0.93 deploy=high replacement=none subsystem=clocksource category=infrastructure
93%

recommendation

It should stay because this is a core kernel subsystem, not a single legacy driver. The Arm Generic Timer code was still receiving feature work in 2026, the Hyper-V timer code is actively maintained for current virtualized deployments, and both target hardware and hypervisors that ship new in 2025. There is no replacement; removing the directory would leave Linux unable to keep time on most Arm and Hyper-V systems.

repository signals

100 files
30,712 source lines
362 commits, 5y
+7,357 / −3,955 lines added / removed, 5y
151 authors, 5y
monthly commits · 2021-04-21 → 2026-04-21 · 362 total · active in 59/61 months
2021 2022 2023 2024 2025 2026 2021-04: 5 commits · +156 −24 2021-05: 10 commits · +62 −21 2021-06: 5 commits · +20 −10 2021-07: 4 commits · +25 −26 2021-08: 1 commit · +1 −0 2021-09: 2 commits · +12 −3 2021-10: 12 commits · +159 −106 2021-11: 8 commits · +82 −28 2021-12: 9 commits · +272 −9 2022-01: 2 commits · +2 −3 2022-02: 7 commits · +35 −607 2022-03: 7 commits · +11 −288 2022-04: 6 commits · +294 −29 2022-05: 16 commits · +247 −68 2022-06: 8 commits · +216 −48 2022-07: 8 commits · +559 −5 2022-08: 9 commits · +436 −259 2022-09: 7 commits · +18 −8 2022-10: 5 commits · +37 −17 2022-11: 13 commits · +141 −71 2022-12: 3 commits · +10 −3 2023-01: 3 commits · +12 −7 2023-02: 6 commits · +22 −19 2023-03: 19 commits · +271 −233 2023-04: 5 commits · +44 −17 2023-05: 6 commits · +366 −74 2023-06: 7 commits · +197 −545 2023-07: 6 commits · +33 −15 2023-08: 2 commits · +2 −4 2023-09: 3 commits · +208 −2 2023-10: 6 commits · +72 −21 2023-11: 2 commits · +9 −2 2023-12: 3 commits · +19 −11 2024-01: 3 commits · +4 −4 2024-02: 10 commits · +127 −73 2024-03: 4 commits · +6 −2 2024-04: 1 commit · +0 −1 2024-05: 1 commit · +1 −1 2024-06: 3 commits · +27 −9 2024-07: 8 commits · +335 −11 2024-08: 8 commits · +79 −45 2024-09: 2 commits · +16 −5 2024-10: 12 commits · +208 −52 2024-11: 3 commits · +5 −5 2024-12: 1 commit · +3 −3 2025-01: 1 commit · +3 −3 2025-02: 6 commits · +53 −8 2025-03: 1 commit · +1 −3 2025-04: 4 commits · +564 −9 2025-05: 6 commits · +313 −40 2025-06: 11 commits · +29 −13 2025-07: 2 commits · +2 −2 2025-08: 32 commits · +1,107 −852 2025-09: 1 commit · +59 −25 2025-10: 5 commits · +30 −51 2025-11: 7 commits · +194 −10 2025-12: 5 commits · +14 −40 2026-01: 3 commits · +5 −1 2026-02: 5 commits · +85 −91 2026-03: 0 commits · +0 −0 2026-04: 0 commits · +0 −0

sources

  1. lore.kernel.org

    `drivers/clocksource/arm_arch_timer.c` had upstream feature work in March 2026, showing the subsystem is still actively maintained for current Arm platforms.

  2. lore.kernel.org

    `drivers/clocksource/hyperv_timer.c` was still being touched by Hyper-V/paravirt work in January 2026, indicating ongoing relevance for current virtualized deployments.

  3. developer.arm.com

    Arm's Generic Timer is a standardized timer framework for Arm cores, evidence that at least part of this directory targets contemporary Arm systems still shipping new.

  4. learn.microsoft.com

    Microsoft's current Hyper-V TLFS documents active synthetic/reference timer facilities used by present-day Hyper-V guests, supporting ongoing deployment of relevant Linux clocksource drivers.

codex reasoning notes (technical)

Not a single legacy device driver but an active subsystem containing many platform timer drivers. MCP `lore_file_timeline` on `drivers/clocksource/arm_arch_timer.c` and `drivers/clocksource/hyperv_timer.c` showed heavy 2021-2026 traffic and recent 2026 touches, with no evident removal/deprecation signal in the sampled lore evidence. Web search found current Arm Generic Timer and Microsoft Hyper-V timer documentation, showing this code covers hardware/VM timer blocks still used in new systems. No single upstream replacement exists for the directory-wide use case.