drivers/sbus/char

Sun/Oracle SPARC platform service devices and Oracle DAX accelerator

A grab bag of small character devices for Sun and Oracle SPARC machines: the OpenBoot PROM interface, environmental and flash controllers, a seven-segment status display on CompactPCI boards, the Tadpole laptop microcontroller, and Oracle's Data Analytics Accelerator engines in SPARC M7/M8 CPUs. Most target 1990s-2000s Sun gear; DAX is in current Oracle servers.

keep-annotate conf=0.67 last_sold=2021 deploy=low replacement=none subsystem=sbus category=platform-vendor
67%

recommendation

Worth keeping but flagging as a niche legacy corner. The directory still sees occasional upstream maintenance — OpenPROM received a bug-fix patch as recently as 2025 — and the Oracle DAX engine remains relevant to current SPARC M8/T8 servers, so there is no removal pressure. However, almost everything else here targets long-obsolete Sun hardware like CompactPCI CP1400 boards and Tadpole laptops, so documenting which pieces are vestigial versus still-shipping would help future cleanup.

repository signals

12 files
4,902 source lines
19 commits, 5y
+63 / −73 lines added / removed, 5y
12 authors, 5y
monthly commits · 2021-04-21 → 2026-04-21 · 19 total · active in 11/61 months
2021 2022 2023 2024 2025 2026 2021-04: 0 commits · +0 −0 2021-05: 0 commits · +0 −0 2021-06: 0 commits · +0 −0 2021-07: 0 commits · +0 −0 2021-08: 0 commits · +0 −0 2021-09: 0 commits · +0 −0 2021-10: 0 commits · +0 −0 2021-11: 0 commits · +0 −0 2021-12: 0 commits · +0 −0 2022-01: 0 commits · +0 −0 2022-02: 0 commits · +0 −0 2022-03: 0 commits · +0 −0 2022-04: 0 commits · +0 −0 2022-05: 0 commits · +0 −0 2022-06: 0 commits · +0 −0 2022-07: 0 commits · +0 −0 2022-08: 0 commits · +0 −0 2022-09: 0 commits · +0 −0 2022-10: 1 commit · +2 −2 2022-11: 0 commits · +0 −0 2022-12: 0 commits · +0 −0 2023-01: 1 commit · +1 −1 2023-02: 0 commits · +0 −0 2023-03: 3 commits · +4 −5 2023-04: 0 commits · +0 −0 2023-05: 0 commits · +0 −0 2023-06: 1 commit · +10 −11 2023-07: 1 commit · +7 −7 2023-08: 0 commits · +0 −0 2023-09: 0 commits · +0 −0 2023-10: 0 commits · +0 −0 2023-11: 0 commits · +0 −0 2023-12: 0 commits · +0 −0 2024-01: 0 commits · +0 −0 2024-02: 1 commit · +1 −1 2024-03: 6 commits · +13 −22 2024-04: 0 commits · +0 −0 2024-05: 0 commits · +0 −0 2024-06: 1 commit · +4 −0 2024-07: 0 commits · +0 −0 2024-08: 0 commits · +0 −0 2024-09: 1 commit · +0 −2 2024-10: 0 commits · +0 −0 2024-11: 0 commits · +0 −0 2024-12: 1 commit · +5 −5 2025-01: 0 commits · +0 −0 2025-02: 0 commits · +0 −0 2025-03: 0 commits · +0 −0 2025-04: 0 commits · +0 −0 2025-05: 0 commits · +0 −0 2025-06: 0 commits · +0 −0 2025-07: 0 commits · +0 −0 2025-08: 0 commits · +0 −0 2025-09: 0 commits · +0 −0 2025-10: 0 commits · +0 −0 2025-11: 0 commits · +0 −0 2025-12: 0 commits · +0 −0 2026-01: 0 commits · +0 −0 2026-02: 2 commits · +16 −17 2026-03: 0 commits · +0 −0 2026-04: 0 commits · +0 −0

sources

  1. lore.kernel.org

    `drivers/sbus/char/openprom.c` still received an upstream bug-fix patch in 2025, so the directory is not abandoned upstream.

  2. oracle.com

    Oracle's SPARC server page still advertised SPARC M8/T8-era systems and explicitly mentioned data analytics accelerators, indicating at least some in-directory hardware remained commercially positioned in the 2020s.

  3. oracle.com

    Oracle's SPARC M8 processor datasheet says the chip incorporates on-chip Data Analytics Accelerator (DAX) engines, directly matching `oradax.c`.

  4. dogemicrosystems.ca

    The CP1400 board named by `display7seg.c` is a legacy Sun CompactPCI board, supporting the conclusion that much of the directory targets old SPARC platform-management hardware.

codex reasoning notes (technical)

Mixed legacy SPARC service-driver directory: `openprom`, flash/envctrl/i2c, 7-seg, Tadpole microcontroller, plus Oracle DAX. Lore evidence came from `lore_file_timeline(path=drivers/sbus/char/openprom.c)`, which showed 2022-2025 activity and yielded the cited lore URL; I found no positive removal signal, only ongoing maintenance. Hardware evidence came from local source/Kconfig inspection plus web search URLs: Oracle M8/T8 pages and the M8 DAX datasheet tie `oradax.c` to relatively newer but niche enterprise SPARC systems, while the CP1400 handbook confirms other covered devices are long-legacy. Net: not a removal candidate, but strongly legacy overall, so keep with annotation rather than deprecate/remove.